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    Infloor Radiant Heat issue (177 Posts)

  • RCO RCO @ 8:33 PM
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    Infloor Radiant Heat issue

    Hello.  We just recently purchased a property that has this system in the concrete slab.  The cottage is under 1000 sq ft and has 2 loops in the floor with an Electromate electric boiler.  The problem we are having is that the system can't maintain the set temp of 68 or 69 once it gets dark at night.  The temp will drop 6 - 8 degrees and won't catch back up until late AM the next day.  Of course we realize that it takes the system sometime to heat up from the 55 degree setting we keep it at when we are not there.  We have found a solution to this situation as a neighbor is going to turn the heat up 10 - 12 hours before our arrival.  But the 3 times we spent there thus far, the system will be right on at the set temp during the day but drops at night. 
    We have a vaulted ceiling which is 23 ft in height.  One half of the cottage has a loft above.  We also have 3 windows side by side on both the northwest  and northeast corner as well as 6 windows (3 on each side) on the north side.  These are quality Andersen double pane units.  This property was completed in 2009 by the former owner.  We understand from the builder that their is R19 insulation in the ceiling. 
    We had a local plumbing/heating contractor recommended by our realtor in to inspect the system.  We had to do this via phone and help from our realtor as we are 275 miles away.  The contractor indicated that the system seemed to be working as it should and seemed to be sized adequately for the square footage.  He spoke with a contact at the local electric provider to find out what setup for usage we were at...restricted or unrestricted.  We have no restrictions and, of course, are paying the higher rate for electricity as we don't have a dual fuel source.  His recommendation was to install a gas wall heater to assist the radiant heat in keeping up.  His opinion was that even though the system was adequate for the square footage.  It didn't account for the vaulted ceiling, loft area, windows, and lower insulation value of this type of ceiling.  His recommendation with the gas heat was to enable us to have a lower electric rate for our heat to bring the electric costs down. 
    I believe that is one option.  However, it doesn't address the inefficiency or inabilility of the current radiant system keeping up with the demand.  I'm not sure I want to spend the $2000 - 2500 to install this gas heat, tank, and meter/electric hookup to see how this will work.  There is also the unknown as to how much gas we will be using to supplement the system.  The other issue is the space for the gas heater.
    I realize that I don't have a lot of info regarding the current system but plan to find out the boiler size and take pictures if necessary.  I've talked to various contractors, company reps, and other owners of radiant heat systems.  I guess there are just too many variables to give different views on the problem.  We plan on talking with the builder and hopefully the cement contractor to see if the slab was insulated properly.  I've been told that you would be able to see heat loss around the foundation if it wasn't insulated on the sides and also the reverse.   That the heat would go down into the ground??  I also do not see any snow melting off the roof of the property so it must be fairly well insulated.
    Anyway, in closing, I would appreciate any help, suggestions, things to check for, or other advise you might have.
    Thank you!
  • Mark Eatherton Mark Eatherton @ 10:00 PM
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    Need lots more information...

    Need boiler model/size.

    Need pump size.

    Need actual square footage served.

    A heat loss calculation should have been performed by someone. Check with the GC and see if you can get a copy of it.

    It might also be a good idea to have a blower door test performed on the dwelling to see if there are a lot of air leakage issues.

    Some boiler room photographs would be helpful as well, showing the near boiler
    piping.

    As far as slow reaction is concerned, there are numerous devices on the market that will allow you to call your house and turn the system up before you get there. It will also call you if the homes interior drops below a certain adjustable temperature.

    Get back to us.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Gordy Gordy @ 11:07 PM
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    dwelling location

     I'm not a professional as Mark is, but just some thoughts.

    With key words like cottage, 1000 sf, loft, and expansive north facing glass which is not ideal to have. Would this be a lake/river view property, or some type of mountain view location?
     
       If so could it have been built as a summer occupancy only property with a heating system designed to get through shoulder heating months only to be closed up for dead of winter retreat?
     
     Does the heating system contain a glycol mixture instead of straight water?
     
     
     Is the 1000 sf including the loft? If so how many radiant sf on the main floor.
     
     What size (diameter) is the tubing supplying the slab?
     
     Btu output of electric boiler?
     
     Floor coverings what kind?
     
     
     The two loops need be figured out for spacing to the sf of main floor. With only two could be wide center spacing, really long loops with close spacing, or smaller sf covered then I'm thinking. Right now guessing 250sf loft 750sf main floor.
     
     If dimensions are as I think that is two loops at 375' each with 1' spacing, or 15" spacing at 300' each loop. 
     
     Trying to get in the system designers head is part of the task.
     
    Gordy
  • RCO RCO @ 7:40 AM
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    Heat Issue

    Thank you for the quick response to my issue.  I'm heading up there this weekend so will try to obtain the info requested.  The floor covering is ceramic tile.  At this point, it is a weekend/vacation home.  The original owner built to use in all seasons.  Unfortunately, the heating contractor is no longer in the area so can't go to him for any info.  I also forgot to mention that I believe the thermostat is a standard air temp unit.  I've read where a person should use slab thermostats for this type of heat??
    Thank you!
  • RCO RCO @ 7:43 AM
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    heat issue

    Sorry....forgot to mention that this property is not on a lake......a 1/4 mile from the lake.  It is in the woods so wind isn't as big an issue as say where my permanent home is in South Dakota!  The location is in N Minnesota so temps can get rather cold.
  • Gordy Gordy @ 9:50 AM
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    Thats a start

     Ceramic tile is radiant friendly so no high r value floor coverings is a plus. Being sheltered in the woods good also.  So I can assume the north facing glass is do to lot orientation.  Are you sure the R 19 insulation is not the walls instead of the roof?
    Even though its cathedral you should be able to get at least an r 30-38 in the roof. R 19 in the roof is not much for northern MN. If he designed for year around occupancy.

     Double check to see if the slab at least has perimeter insulation installed you should be able to visually see that. It may be covered with a skirting material.

    Gordy
    This post was edited by an admin on February 24, 2011 9:53 AM.
  • Jean-David Beyer Jean-David Beyer @ 9:28 AM
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    In floor radiant...

    I have that too; copper tubes in a concrete slab. One thing to be aware of is that if you change your set point, it takes 3 to 6 hours (YMMV) to notice the effect, and 12 to 24 hours for the system to re-stabilize, due to the high thermal mass of the slab. So I hope your system has outdoor reset and that it can be adjusted properly.

    One reason for using outdoor reset is so that as the outdoor temperature drops, the water temperature in the slab can be increased even before your house gets too cold. Of course if your boiler is already going at its maximum, outdoor reset will not get any more out of it. And you will probably not want to put more than 120F water into the slab anyway. For this to be most helpful, it helps if you adjust the reset curve so the circulator runs a lot of the time; e.g., 12 to 18 hours a day. Some people advocate 24 hours a day, but I do not do that. But I am not a professional, so I have experience only with my own boiler. For my system, doing setbacks in the zone heated by the slab does not make sense except for vacations when I will not be here because the recovery time is so long. Before I thought about it, I had to start the night setback around lunch time, and the recovery for the next day around 10 PM. Even that was not satisfactory because the outdoor temperature does not change the same every day, and if the inside temperature does not drop enough, the boiler and circulators do not run. I do a little setback in my upstairs (baseboard) zone, but even there, I do only 2F of setback and it takes quite a while to recover since I use low water temperatures in the baseboard.

    About having a neighbor turning on the heat before you get there. It is probably a good idea to have that done the day before you get there. I have an alternative, a thermostat that can do a setback for up to 255 days and at the end of the setback it will turn on the heat in the morning, daytime, evening, or night. It is a Honeywell CT3600; However it is discontinued. It looks as though a VisionPRO 8000 7-Day Programmable Thermostat will do this.
  • Gordy Gordy @ 10:05 AM
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    Good points

     JDB, But they are reaching setpoint during the day, and losing it over night.  And they are bringing the slab up from a 55* set point. Not a real cold start up but if the system is border line to the load its a chug. We do not know conditions as far as outdoor temps, how long occupied while the problem is occuring.

     IF no insulation under slab then there is a heat sink issue to overcome. No perimeter insulation heat sink just got bigger.

    Gordy
    This post was edited by an admin on February 24, 2011 10:07 AM.
  • Jean-David Beyer Jean-David Beyer @ 12:04 PM
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    Two different issues.

    I think we all lack sufficient information about the system in question. Heat loss? Amount of radiation, insulation, presense or absense of reset an how it is adjusted if present, etc.

    There seem to be two issues.

    1.) Time to recover from long setback to 55F. With a concrete slab, at least like mine, that would take over 24 hours to recover. Once my old boiler quit sometime late Friday or Saturday and they did not come to fix it until Monday morning. My house is quite well insulated, so the temperature did not become objectionable unitl Sunday night, and I resorted to sweaters and an extra blanket at night. Once the problem was fixed, heat started, but it was not until sometime during the day Tuesday that things were back to normal. That boiler burned 70,000 BTU/hr and my heat loss is less than 35,000 BTU/hr, so I definitely had enough heating capacity, but I did not wish to turn up the water temperature and burn my feet. About the only solution I can think of is to turn on the heat a day or so before he comes home, either by having a friend do it, or by getting a fancy thermostat to do it.

    2.) If he has barely enough boiler, or barely enough radiation, so he can maintain the setpoint during the day but not at night, we cannot escape the need for the heat loss study results. It may be hopeless with the current system (without changes). If it is only slightly marginal, it might be that he could set up the system to pump most of the time, with the boiler modulated way down, and as it gets colder outside, have the outdoor reset turn up the water temperature to get a head start at warming up the slab for night time.
  • RCO RCO @ 10:58 PM
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    More Information

    Hello.  Just spent the weekend at our place.  I have a correction as far as the make of the boiler.  It is a Thermolec boiler, model B10U-M, which has the capacity to produce 34,120 BTU's.  I'm not sure how we came up with ElectroMate???- possibly the contractor had inadvertently said that brand.  Anyway, we spoke with the contractor on Friday afternoon.  He indicated that there are 3 loops in the slab.  He said the most heat you will ever get out of that system is 27,000 BTU.  It may be sufficient for the square footage based on 8 foot ceilings.  But with the vaulted ceiling, loft, and window area, it is just not enough.  I asked what he would have done had he been the contractor during construction.  He mentioned he probably would have gone with in floor heat in the loft as well which would have required a larger boiler. 
    So we are trying to determine our next step to solve our heating issue.  I did take several measurements and I'm going to give the info to our electric coop so they can do a heat loss analysis.   The square footage of the main level is 720 sq ft (24' x 30").  The peak is 23 ft and walls in the open area are 10'8".  This area is around 14' x 24".  So 16' x 24' consists of the kitchen area, utility closet, bedroom and closets, bathroom, and hallway.  This is all under the loft which has a 9 foot ceiling.  The loft area is around 235 square feet.  It has a 10' x 15" area as well as a 6' x14' area which includes the stairway.  The height of the ceiling in the loft is 11' 6". 
    I have a difficult time with directions when back in the woods area.  It appears that the home is mostly facing east to southeast.  There are 2 windows on the front side - 1 bedroom and 1 bathroom that are 30" x 58" and front door that is 36" x 80" with 2' x 3' glass area.  The loft has 2 small windows side by side on the front that are 22" x 22".  The backside which would face west to northwest has 2 windows on each side of the fireplace for a total of 4.  They are 34" x 70" each.  On each side in the back corners are 4 windows facing south to southwest and north to northeast for a total of 8.  These are 22" x 70" each.  There is a side door on the north side into a screen porch.  This is a 36" x 80" door with a 2' x 4' glass area.  Above the back windows on each side of the fireplace are 2 windows (total of 4) - a triangle shaped unit that is 30" x 30" x 42" and a trapezoid that is 40" x 32" x 66" x 36".  The fireplace is a 76" wide x 23" tall by 30" deep construction with cultured stone applied.  This is a wood burning unit.  Also the insulation is R38 in the ceiling and R19 in the walls as confirmed by the builder.  He also confirmed that the slab was insulated below the heat tubing as well as around the perimeter of the slab.  I believe that I have everything I could think of in measurements. 
    The heating contractor suggested that we do install a slab thermostat so we could use some other source of heat such as the fireplace or infrared heater without have an impact on the thermostat as we would on the current stat.  He agreed with us that we really don't have a lot of room to place a gas wall heater so suggested we look into electric panels for the loft.  We are currently paying $.09 per kwh (raising to $.0943 in April) for electric as we do not have a dual fuel source.  So we would need to look at a gas (propane) supplemental heat to qualify for this rate which is $.0526 (increasing to $.0552 in April).  I did get some pictures of the current system but haven't downloaded them as of yet. 
    So, that pretty much lays it out as to what we're dealing with on our heating issue. 
    Thanks!
  • Mark Eatherton Mark Eatherton @ 11:28 PM
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    Something's not right...

    I come up with around 34 btu/sq ft/hr which should be MORE than enough to keep your home warm. At that rate, you should have floor temperatures of 85 degrees F.

    I also disagree with the contractor about the output of the boiler. It appears that he is derating an electric boiler by 20%, which is pure bunk. You don't derate the output o an electric boiler. It is 99.99% efficient.

    I'm thinking that you have some elements that are fried, or a contactor that is not pulling in, or a control that is not properly set. Depending upon the R value of floor finishes, the operating temperature of the boiler should be between 110 and 140 degrees F.

    You didn't happen to look at the temperature and pressure gage to see what temp it is running did you?

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Gordy Gordy @ 11:43 PM
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    Output

     Mark,

      Could it be he is basing his 27000 btu's by sf output?  720 sf of radiant floor at 35 btus sf is 25200 btus capacity If the floor temps are 85*. So he may be basing on a little higher floor temps.

      But you will lose some of that available output floor minusing kitchen base cabinets closets etc. Even if the tubing were layed out underneath them.

     Another BUT is it is all done right good insulation for structure. Slab is insulated etc. Sounds like good window orientation to capture winter sun, better than north facing.  So the heat loss should not be that much for 1000 sf structure of that type of build. And I do agree that the floor is not meeting its full output potential.

     So I do agree something is not right.  The boiler has the capacity to meet that load.  I also agree some supplemental in the loft area may be helpful. Panel rads maybe. 

     MRT is probably laging with a 12 hour fire up window to get things warmed up could have some effect, but not for long.


      Gordy
    This post was edited by an admin on February 28, 2011 11:47 PM.
  • Mark Eatherton Mark Eatherton @ 8:06 AM
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    Theoretical versus Reality...

    I hear what you are saying Gordy, and in a sense you are probably correct. However, the reality of the matter is that it is a well built/insulated home, with a load more likely less than 20 btu/sq ft/hr (except possibly for mega infiltration beyond the end users control) and it is a well know, documented fact that when coming out of a deep set back, that the slab will suck up every BTU thrown at it until things get stabilized.

    The reality of the matter is, that the space is dropping considerably at night, and it shouldn't. The daily energy load shouldn't change that much between day and night, except for solar gains. I suspect dead electrical elements in the boiler... There are enough to handle the day time loads, but not enough to carry it through the night.

    And you are correct, that the loft could probably use some emitters to increase human comfort in close proximity. The GC was probably going under the impression that radiant heat "Rises". Fiddle faddled by the misguided finger of fate...

    When the wood stove is running, convection will kick in, and it's heat WILL rise, probably to the point of discomfort. Shoulda installed a destratification fan...

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Gordy Gordy @ 8:54 AM
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    Agreed Mark

      Would like to see the pics.  One other simplistic question would be where is the thermostat located?  Could it be in a location that could give false ambient readings by day, or night for that matter?  Is it possible that the tstat could be slipping in to a set back setting at night that the user did not realize was happening?

     Gotta cover all the bases

    Gordy
  • RCO RCO @ 3:09 PM
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    More Info

    Thanks guys for the feedback!  I'm attaching pictures of the heating system I took this weekend.  If they are clear enough the water temp should be visible on the gauge.  I may have inaccurately explained what the contractor was saying.  He indicated that do to the amount of lines in the floor, the most the slab would ever produce is 27,000 BTU's, I believe. 
    The thermostat is located on the corner of the entrance hallway.  However, it is outside the closet that houses the heating system.  Another question I have is whether or not area rugs would make a difference on suppressing the heat from the floor?  We have an 8 x 10 wool rug down in the main living area.  I think I mentioned in an earlier post that we have ceramic tile throughout the main floor.  There is also a 3 x 8 rug in the hallway. 
    I've probably posted more than enough attachments for this post.  I can post pictures of the interior and exterior of the home if needed. Again, this system is just around 1.5 years old as the home was finished in the fall of 2009.  But I would imagine that failure in the boiler could happen at anytime.  Possibly it could still be under warranty??
    Thanks again!
  • Gordy Gordy @ 4:32 PM
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    Rugs

     Do reduce output its like throwing a piece of insulation over the floor. Remember the floor is your heat emitter. And wool to boot. About 104 sf of reduced output area. Not a huge deal, maybe 3640 btus. 

     Temp gauge on boiler is saying 120* at that moment could stand to be higher130- 135ish.  It would be nice to know the reading on the temp gauges at the manifold supply, and return also.  flow meters appear to be in the half way range.

      More visual stimulation never hurt anything. share more pics if you wish.


    Gordy
    This post was edited by an admin on March 1, 2011 4:35 PM.
  • Jean-David Beyer Jean-David Beyer @ 8:20 AM
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    Come to think of it, ...

    Is the pressure not kind-of high, too? Looks like maybe 30 psi. Hard to be sure, blurry and all. This would have nothing to do with the problems, but should be looked into.
  • RCO RCO @ 8:36 PM
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    Some more info

    Here are a few pictures of the property - inside and out as well as a spreadsheet showing electric usage from 12/19/10 - 2/1/11 for whatever its worth.  If I understand, it would be a good idea to possibly roll up the rugs and store for the winter to keep from blocking the heat?  Would it be worthwhile to go with a slab stat in place of an air temp stat?  I suppose there is some risk in hitting a line trying to drill for the sensor at this stage of the game??  I hope the pictures of system and property will assist in helping solve the problem.
    Thanks!
  • Gordy Gordy @ 11:16 PM
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    Very nice

        I would do a floor sensing thermostat. 
       Your loop lengths should be fine 3 loops at 1' centers is 240' each loop, or could even be 9" centers at 312' each if 1/2' dia. tubing should be just fine either way may even be 5/8" better yet. This all has to do with the pumping head generated by the friction of the water flowing through the tubing. The longer the tubing loops the more head loss, and the smaller the dia the more head loss. glycol in the system also contributes to head loss
        If you want to find the center spacing. Buy a cheap infrared thermometer 50 bucks. Run it across the floor to find the hottest spot then move until the next peak hot spot. You may have to spend some time in an area to get the jest of which way the tubing is laid. The thermometer will also assist in putting in a sensor, and checking floor temps all around the floor.

        Heavier grade window treatments do wonders in reducing heat loads. Closing window treatments during night time hours can reduce heat loss dramatically. A long with controlling summer time heat gains.

        One other question I would like to ask is what thickness was the concrete floor poured?  The thicker the more mass to warm up even though it is insulated.

        I do not think you have real serious issues. Just think things need dialed in, and make sure the boiler is functioning properly.

     So step one is make sure Boiler is functioning properly as Mark stated earlier.
     Step two make sure the loops are purged of any air.



        Check floor temps with an infra red thermometer to see what they actually are. Check all around the main floor for even temps. a cold section could indicate a loop that is not getting enough flow, or air bound. Once you get a feel for the loop layout you can even find where the loop starts being the warmest, and where it ends being cooler.

        See what supply return temps are at the thermometers mounted on the manifold there should be about a 10-20 degree difference or delta T in the supply, and return temps say 130* supply and 110* return. This needs to be done once the system is steady state. When its coming up to temp out of set back that number (delta T) will be quite a bit larger, and diminish as the system gets closer to steady state when the thermostat is actually satisfied.

      What I would do is observe the system once at steady state say 68* tstat setting. Wait for the next heat call. When it goes check temps at the boiler, then the supply manifold, and then the return manifold. watch them through the whole heat call until the tstat is satisfied. If at the end of the heat call the delta t is 10* to 20* at the supply, and return manifolds. then you have good flow, and you need to bump up the temp of the boiler a little more.  If you have a large delta t more than 20 then you may need to increase flow at the flow meters. It takes time so be patient.

     If you make adjustments let them work for a day or so. There is a lot of mass so changes are not instantaneous. But the slab being insulated does make it more responsive then a slab with no insulation.

    Gordy

     

     
    This post was edited by an admin on March 1, 2011 11:22 PM.
  • RobbieDo RobbieDo @ 9:20 PM
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    Just my opinion

    I don't like putting the pump that close to the air scoop. Is this pumping away from the scoop, I can't tell? After the pump looks like it goes right to a 90? Well, anyway this isn't a real huge issue I just don't do it that way. You said there was 3 loops in the slab, is that 1/2"? How long are the loops?
    Rob
  • Mark Eatherton Mark Eatherton @ 11:21 PM
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    It is supposed to be as close the the scoop/expansion tank as possible.

    What is your reasoning for NOT wanting to put it there?

    More to the point, the operating temperature of the boiler , if in fact it was operating when the photo was taken, is a little low. I'd crank it up to around 130 degrees F. If it can't achieve those temperatures, then there is definitely an issue with the elements.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • RobbieDo RobbieDo @ 5:23 AM
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    Issues

    Mark, I have had issues with air if it's that close, just from my experience. After I spoke with the Mfg. they recommended I move the pump father away during installation. Seemed to work have been doing it that way since.
    Rob
  • Mark Eatherton Mark Eatherton @ 11:41 AM
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    Your milage may vary...

    I guess we all have different opinions and field experiences. I have been parking the pumps inlet as close as possible, and have not had any issues that you are having. What happens if there is any considerable distance between the inlet of the pump and the expansion tank is that a pressure DROOP occurs between the expansion tank and the pumps inlet. THis droop in pressure, can in some cases, cause oxygen to JUMP out of the water, thereby compounding any entrained air issues, and or cavitation issues on start up.

    With that said, I have seen systems that were TOTALLY screwed up that still produce circulation and heat. Noisy as all get out, but still had circulation and heat. Heat is not necessarily comfort, but is a required component of comfort.

    I used to believe that conventional air scoop (and still do) were adequate for good air elimination, but have come to realize that MBR's are significantly more efficient at initial air removal, so this old dog has started using more of the MBR's as opposed to scoops.

    I don't subscribe to some of the manufacturers claims that their devices are so good at air removal that they will suck air off the next closest planet with oxygen, nor will they address any trapped air at the top of the system. That comes down to good field practice in getting rid of the free air on initial purge. If you don't do a good job of that, you can expect ongoing problems with air.

    As long as we aren't talking feet of pipe between the expansion tank and the inlet you will probably be fine...

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Jean-David Beyer Jean-David Beyer @ 12:58 PM
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    I happen to believe...

    ... that microbubble rmovers are better than plain air scoops, especially for a dumb installation like mine with baseboard upstairs and no air bleed vents up there. But I am not a professionial, so I doubt my opinion has all that much weight.

    But one advantage of my Taco 4900 series, and I believe the Spirovent, is that there need be no straight run either before or after the device, and no need for a directional arrow on the device either.
  • Mark Eatherton Mark Eatherton @ 4:07 PM
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    Belief Busters..

    JD, I worked with a forensic engineering group out in California during my work as an expert witness on the Entran 2 trials. They tested the MBR against the conventional air scoop and determined that they both took the water to the same o2 content. The MBR did in fact get there quicker, but it didn't remove any more oxygen than the scoop did.

    As for straight pipe, I have seen one manufacturer that recommended the straight pipe requirement before and after their device. THeir assumption is that in a district loop heating system, the water will be flowing at maximum velocity ALL of the time. In residential space heating systems with zone valves, that occurs for 2 % of the time.

    I have piped directly from a riser, through an elbow and directly into a scoop and not had problems, but have heard of one system that did have issues with that configuration.

    Your opinion is always welcome here. You bring a unique perspective to the class :-)

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Jean-David Beyer Jean-David Beyer @ 5:33 PM
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    I would not argue with an expert witness.

    And since I have a microbubble remover in there, there is no point removing it.

    Where it is is straight for a few inches on either side. The manufacturer says to keep the flow through it to less than 5 feet per second. My boiler manufacturer says to use at least one-inch pipe there, and my contractor used 1 1/4 inch, so that should reduce the speed. One zone runs 2.4 gpm (calculated, not measured) and the other runs something else -- I cannot tell what because it is mostly 1/2 inch copper tubing in a slab and I have no idea as to the length, driven by a Taco 007-IFC. The floor area is about 750 square feet and is five parallel circuits of unknown length. I suppose it is more than the other zone since the 5 tubes entering return through a 1-inch one, and the heat load there is about 4 times the other zone.

    It is not constant flow. Sometimes both circulators (no zone valves) run, and sometimes just one.

    "You bring a unique perspective to the class :-)"

    I like that. For me this web site really is a class.
  • Steamfitter66 Steamfitter66 @ 2:29 PM
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    Good piping practice is

    4X pipe diameter of straight pipe on supply and discharge of pump and control valves. If velocity is over 4 fps then 6x.
  • RCO RCO @ 3:28 PM
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    Followup

    Mark
    Concerning the question in regards to whether or not the system was operating at the time of photo.  Yes, it was approximately 10:45 AM about the same time I took a picture of the thermostat.  You can see the temp on that which had dropped down slightly lower than this temp the night prior. 
    Would it be good advice to get a 2nd opinion from another contractor to check out the boiler?  Again, it's not very old...but can't contact the original contractor either to see how it was set up. 
    Thanks!
  • Mark Eatherton Mark Eatherton @ 4:01 PM
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    Follow up to your follow up :-)

    Here is a link to the O&M manual for your boiler.

    http://issuu.com/thermolec/docs/thermolec_electric_boiler_manual

    It appears that there are 2 5 KW elements, so it is entirely possible that you have a dead one. However, it also appears that your boiler comes with an outdoor reset, and it may be set to low.

    Have the service agent follow the instructions for troubleshooting as spelled out in the manual, and if everything proves functional, then have him increase the minimum or maximum settings to get warmer water out of the appliance.

    I would go with 95 degrees F at minimum and 130 degrees F maximum. That should keep you in a comfortable condition. Also, depending upon what the outside air temperature is doing when it is coming out of a deep set back during unoccupied conditions, as it gets warmer outside, it could take even longer to get the place up to temp, but theoretically, it shouldn't because the demand for heat is less.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • RobbieDo RobbieDo @ 3:37 PM
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    Pumping away

    I install so the pump is approx. 8"-12" away from Spirovent. That is just the issues I have had.
    Rob
  • jp jp @ 5:38 PM
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    insufficient insulation

    I suspect insufficient floor or perimeter insulation.  you have some pretty good low  outdoor temps. 2 inches of foam doesn't do well faced with single digit temps.   correcting perimeter insulation might make a big difference.

    try to find out how the place was insulated, get a "sketch" of what they did around the foundation, don't let them just tell you.  

    if the tstat isn' t satisfied the system should never shut off.   if you turn the pump off, the boiler will go up to the set point temp and turn off.  that will tell you what the boiler is trying to achieve or if it is achieving its set point.   you have those little temp gauges on supply & return with those little flow meters, so you can figure out(estimate)  btu's into the floor.

    check your water temps morning, mid day, and late evening.  maybe there is a night time set back working you are not aware of?

    a floor sensor is a waste at this point, wait til you get the room temps where they need to be.

    measuring floor temps at various places will give you more info on whats really happening too.

    to me, 120F supply water on a slab home seems high if you aren't below zero F.

    I like this idea for insulation.  from mich residential code book.
    This post was edited by an admin on March 2, 2011 6:15 PM.
  • Gordy Gordy @ 8:48 PM
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    Slab insulation detail

     JP,
      That detail shows nothing under the slab for insulation??

      Not to say its right to do, but I have seen a lot of radiant slabs with NO insulation perform well, and able to heat the structure.  Efficient no, Able to perform yes.

      I think Mark is on the right path.

    Gordy
    This post was edited by an admin on March 2, 2011 8:51 PM.
  • RCO RCO @ 10:35 PM
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    Appreciate all the input

    Thanks to all for your comments and suggestions.  Mark, I appreciate the manual on the boiler.  The only info I had from the previous owner was the installation instructions that were left with other info on appliances, etc.  jp, I also appreciate the comments on the slab insulation.  However, I'm not sure how I will ever know exactly what insulation was used.  I'll have to take the builder for his word on what he witnessed that it was insulated.  I guess I can contact the contractor who did the concrete work but the heating contractor is no longer in the area. 
    I had a call from the heating contractor we have been working with this afternoon.  He had an estimate for me for installing a TecMark slab stat.  Not sure of the model but his estimate was around $450.  I had just told my wife that I think we should hold off on the stat until we solve the problem of the major heat loss at night.  It was good to see that advice.  I don't believe I want to spend that money and still have the same issues. 
    Mark - I do know that this system has an outdoor sensor.  The reason I know is because the contractor unhooked it as it was buried in the snow.  As a homeowner with very little knowledge of radiant heat, I'm at the mercy of the person whose supposed to be the expert on this type of system.  He indicated that it wasn't functioning as it should buried in the snow and with it unhooked it would put out 120 degree water temp as he set it that way??  Again, I've gained much knowledge in my research but still don't understand the system in all aspects.  I'm assuming that the sensor keeps the water temp regulated by how warm or cold it is outdoors.  But I've a feeling from your comments that it may do more than that?? 
    Our realtor had recommended him to look at the system and I've heard many positive comments about their work.  Just having doubts that he knows this type of system that well.  It's very difficult to work with this issue when we're 4 -5 hours away.  I guess that goes with the territory of owning a cabin/vacation home.  
    From most of the comments made in regards to my issue, I gather that the concenses is this size boiler and loops within the slab should do the job of keeping the heat at the desired temp day and night.  I know there are some things we can do to address some issues, such as add shades to the windows for insulation ( we've discussed that this past week) as well as possibly pull up the rugs during the winter as to not suppress the heat in those areas.  We can also use an infrared heater (Sunheat) for the loft area if need be for comfort. 
    Again, I appreciate the comments and please feel free to add more.
    Thanks!
  • Mark Eatherton Mark Eatherton @ 11:52 PM
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    Tell me more about your fire place...

    It's wood burning, but is it an air tight stove or an open hearth fire place?

    Do you commonly fire it up at night?

    Does it pull outside air for combustion? Does it have glass doors? Do you run it with the doors open or closed?

    Does there seem to be any co relation between the drop in temperature and the use of the fireplace?

    Also, are there a lot of can lights in the ceiling?

    It would appear, based on photographs and newly acquired information (disconnected OSA sensor) that the boiler is working OK, but you could confirm it a couple of ways. One would be to look at the gage when the house is the coldest. Also, on your supply and return manifolds are thermometers. Tell us what they are doing when it is cold in the home.

    Might be worth while to drop a few bucks at home Depot on a non surface contact thermometer so you can see what the floor temperature is, and also look for leaks in the thermal envelope.

    Based on what I read in your manual, the OSA reset only does reset and not set back.

    Hang in there. We will find your comfort. It might just be an induced infiltration issue.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
    This post was edited by an admin on March 2, 2011 11:54 PM.
  • Jean-David Beyer Jean-David Beyer @ 8:08 AM
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    Might be worth while to drop a few bucks at home Depot on a non surface contact thermometer

    How good do these seem to be? Not questioning their temperature accuracy that seems OK, but size of measuring spot, accuracy of the measuring spot vs. where I think it is pointed, etc.

    I have a Black & Decker TLD100 and it seems to work OK, but I really do not think I have been able to find where my copper tubes in my concrete slabs are. Some parts of the floor are warmer, some are cooler, etc, but I do not know that I could tell if I had one foot separation or something else, or if they go lengthwise or widthwise in the room.

    There may be some technique in using the thing that I am unaware of.
  • Mark Eatherton Mark Eatherton @ 9:10 AM
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    Using an IR gun.

    JD, I only use to have the IR non surface contact thermometer. They work great except when reading shiny hot metals, especially copper. If in doubt, cover the pipe with a small piece of masking tape and the emissivity will be corrected.

    Before I had my hand held IR imaging camera, I use to place a grid of masking tape on the floor on 2" centers, and would go through and hold the gun directly at the intersection of tape (actually holding it right on it) and mark the temperatures. A digital image if you will. I would then focus in on the highest numbers on a 1" on center basis to fine tune it. It worked, not as well as my imager, but it gave me a mental picture from which to build upon in my minds eye.

    As for finding tubes in a floor, you have to have "IDEAL" conditions under which to work. First, you must allow the floor to cool WAY Down, like 5 degrees F lower than the normal MRT. This could take days, depending upon the prevailing conditions. Once cooled down, you then turn the stat up, and allow the floor to start coming out of the deep recovery. I find that it needs about 1 hour per inch of slab thickness. At that point, using my IR imager, the lines are very well defined. Start too early, and they are blurred. Start too late, and the heat has dissipated so much that it just looks like a large mass of glowing heat. It's as much art as it is science. If you have an ODR, it is best to bypass that function and hit the slab with as hot a water as you can get.

    In your case, I would check wit the county energy conservation department and see if you can "borrow" their IR imager for a day so you can "see" what is going on.

    FWIW, I got an email from FLIR yesterday. THey now have an imager that starts at $1,200.00. I paid $5K for mine less than 2 years ago! I suspect that the Chinese are getting into the IR imager business, and the American companies are trying to corner the market, but that's just my international conspiring minds theory :-)

    For purposes of just getting a surface temperature, the Cheapo Depot guns work fine for under a hundred bucks.

    HTH

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Jean-David Beyer Jean-David Beyer @ 10:49 AM
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    IR cameras, etc.

    I looked at the current offerings of FLIR cameras. I am AMAZED at how low the prices have gotten. I have to control my equipment junkie tendencies. I have resisted getting a digital combustion analyzer.  I do have a pH meter and an IR thermometer. But as a retired person on fixed income, I should not be spending these monies.

    With my W-M Ultra 3, it is trivial to set the outdoor reset to whatever temperature I want. And since my heat loss when it is 0F outside is well under half the boiler output, I imagine I could put 180F into the slab, though I imagine that would be a really bad idea.

    It occurred to me that I might try this in the late spring or summer. By then, I expect the slab would be no hotter than the ambient temperature, say 80F. I could turn off the warm weather shutdown and diddle the reset curve to get 90F or 100F into the slab.  I would want the windows open, though. Living room would be diffciult (carpet with underlay), but the rest is either ceramic tile, marble tile, or asphalt tile right on top of the concrete slab, Since I am not looking for leaks, but just trying to guess spacing and lengths, this should be good enough, I imagine. I assume all th3 spacing is the same, though I could be wrong, of course.
  • Gordy Gordy @ 6:40 AM
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    Available radiation

     I'm starting to wonder a little about how many sf of furniture, closets, cabinets, and stairways there are verses the 720 sf of radiated floor area.
     We keep thinking max floor output with every sf available.  Deduct 30sf for an enclosed stairway, 28 sf for a couple of couches,  30 sf for some kitchen base cabinets, 18 sf of fireplace built to theinside, and some closets coupled with the 108 sf of area rugs..... thats 214 sf You get down to 20- 21000 btus of max radiation.  A weekend is just a short period of time really to get a stabilized mrt.  That expansive stone fireplace will really soak up some btus

     Just a thought

    Gordy
  • Mark Eatherton Mark Eatherton @ 9:22 AM
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    Maybe, but...

    Gordy,

    EVERY house with RFH has these issues and items in place and rarely suffer daily drops in temperature. It could have some impact on this home due to its occasional occupancy usage, and need for acceleration but in the case of furniture, couches in particular, they slow the flow, but don't stop it.

    I have a high backed couch directly in front of my radiant wall in the mountains, and when I first start it up, the couch is cold, but eventually warms up to around 75 degrees F. It's more a matter of time and MRT coming up and averaging out.

    But as we say, your milage may vary ;-)

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Gordy Gordy @ 8:17 PM
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    Mark

     I do understand what you are saying, and that is my thinking also. Every house has this to over come the mass of the interior space. But, (and I got some junk in my trunk) usually from a light setback maybe 5* verses a large setback of 15*. Then to only come out of that 15* set back for the weekend.  We don't know how thick the slab detail is assuming 6" min. And the depth of the tubing when poured which if deep may have some effect.

     I think the boiler is set low as you do. May have been always that way. or it was turned down to that 120 because un occupied who knows.

     I think some data logging with cheap indoor outdoor thermometers are in order as I stated below. As I said it could be losing temps at night during setback also just don't know it.

      If I were the owner I would even let the heat run for the week to see how it acts upon the week end arrival if it is a routine visit.

     This all could be a combination of small variable adding up to the problem, But I'm just an anal student, maybe even an Arnold Horseshack at times set me straight Mark, I love to be taught.

    Gordy
  • jp jp @ 12:08 PM
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    frost free protection

    Hey gordy,

    I think that diagram was for frost free protection of a slab?  but I like that idea for perimeter insulation, going down deep then outward.

    even those cheapo IR guns give you details of the area it looks at based on distance from target in the directions book.   I'm pretty sure it just picks out the hottest region.   I like my $30 gun.  and the laser pointer is most likely pretty darn close.  so it should work better for finding hot spots opposed to cold spots.

    for starters you can poke around the foundation below the siding.  the chimney side shows part of the foundation below the siding.  if you hit concrete right away, well thats not a good sign.   adding some preimeter insulation wouldn't be that hard.  even if you dug down only a foot and used 3 inch foam.  up here northern mich there was an inspector that FORBID the owners from insulating their perimeter foundation, now they grow flowers year round :)   all thanks to the building inspector.   
  • RCO RCO @ 3:03 PM
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    Wood Burning Fireplace

    I'll try to answer your questions Mark. 
    This is not an airtight unit.  It's a Heatalator brand and has an open hearth with glass doors (not very air tight).  I believe it has an air intake vent on the outside.  We've primarily kept glass doors open until the fire is burning quite well.  But I don't believe I've noticed any difference in drop from either operating it or not.  In fact, the end of January, we started the fireplace later in the evening after our kids got back from town.  The temp had dropped by that point.  So I don't think it has a lot of influence on the heat....my guess anyway.
    I believe we have some canned lights in the kitchen area....I would need to look to make sure.  The vaulted ceiling in the main area has some recessed lighting. 
    When you're talking about the temp readings on the boiler and lines, check those when it drops at night?  I could have my neighbor look at them as it is now.....but the stat is set at 55 degrees.  Although, no one has been there to prove, I believe it is dropping back from 55 degrees when we're not there.  The reason I say this is because my wife found the olive oil coagulated in the kitchen cupboard.  This may be compounded by the fact that I need to address the microwave/hood which is vented to the outside in the screen porch.  The vent is approximately 12" or so long with a hood over top....but no flap to cover when fan not running.  You can feel the cold air under the hood as well as in the microwave.
    I'm adding a few more pics of the layout inside the property.
    Thanks!
  • Gordy Gordy @ 6:23 PM
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    Monitoring temps.

      The easiest way since you are not there all the time is this.

    Buy  4 indoor outdoor thermometers they have a 10' probe. 10 to 15 bucks a piece.

    Take two of them in the boiler room, and tape one probe to the supply pipe by the manifold, and the other to the return pipe on the return manifold with a piece of pipe insulation covering the probe.
     

      These will tell you the minimum and maximum temps each pipe sees over what ever period you check them just don't forget to reset them for the next go around of monitoring. 

      So in other words in place while you are gone for the week, and return for the weekend you can look at the minimum, and the maximum temps that occured while you were gone during the week while the system was in setback on the supply, and return lines. So the max of each probe would be while the system was running, and the minimum on each probe would be probably when the sytem started a heat call.
     
     The differences between the two mx temps would be the delta T, the same goes for the minimum.


     Take the other two thermometers, and set up a couple of feet in from each outside wall in the center of the house put the probe on the floor with a piece of insulation on it. Now these will tell you the minimum, and the maximum temperature the floor achieve while you are gone during set back.

     Now you have a monitoring system that you can check when you go there on the weekend.

     You can also do the same with these while you are there to see how all the temps react during setpoint.

     You could get anal, and get a fifth thermometer for the center of the room also. That way each loop is monitored.

     Those temps would really help trouble shooting how your system is reacting. Because you don't really know if you are losing setpoint at setback temps during the night while you are not there do you.

      Having these thermometers will also save staring at the temp gauges in the boiler room for hours. You can reset them when you go to bed, and check them in the morning to see the highs, and lows the supply, and return temps, and floor areas achieved over night no watching required.

    Gordy

     
    This post was edited by an admin on March 3, 2011 6:36 PM.
  • SWEI SWEI @ 2:52 PM
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    Wood Burning Fireplace

    Forgot to ask - is there a downdraft or other infiltration issues with the fireplace?
  • RCO RCO @ 6:47 PM
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    On Hold Up Until Now

    Hello.  I decided to get back into my search for a resolution to my heating issue.  I've contacted a couple of contractors, one in particular that has installed the Thermolec boilers, to give some input.  The one mentioned is going to meet with us when we get up to our place again this next time.  The other one is telling me from the details I sent that there aren't enough loops in the floor to give sufficient heat.  He claims that the 3 - 300ft loops will only give 18,000 BTUs at most.  I asked if there could be any difference in lines used as the contractor who looked in January indicated that the system was giving a maximum of 27,000 BTU.  He told me that he guaranteed there was no way to get 9,000 BTUs per loop out of the system.  The max would be 5,000 to 6,000 per loop??
    So please tell me how the BTUs are calculated in these systems?  The boiler has the capacity to produce 34,000,  He mentioned that he would probably recommend more radiant panels to feed off the current boiler to help correct the situation.  I just want to be better informed as it appears that I'm being misled by one or both of the contractors that have given their opinion thus far.  Thanks!
  • Mark Eatherton Mark Eatherton @ 10:07 AM
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    Wrong information...

    There is a HUMAN physiology limitation to radiant floors. This limit is 30 btus/square foot per hour (corresponding floor temperature of 85 degrees F, ambient tmeperature of 70 degrees F).

    It is not a physical limitation. With enough boiler, and the right system/conditions, there really is no known "limit" to a floor heat emitter. With in reason (30 btu/sq foot/hour) a 300' loop, at 12" on center tube placement would deliver roughly 9,000 btuH per loop. Again, this is not a physical limitation, but rather a human physiology limitation. If your feet are in contact with a floor that is greater than 85 degrees F, you WILL break out in a sweat. If you don't, there is something SERIOUSLY wrong with your body...

    As we have previously pointed out, you must first make certain that the "system" is working to the fullest extent. If it is, then you need to figure out where the energy is going to.

    Start with the heat source first. Are all elements in good shape? Are all contacts connecting the elements in good shape? Are the controls working correctly? Is the pump moving proper amount of fluid? Are all circuits receiving proper flow? Are all connected thermostats properly set as it pertains to their anticipator settings?

    If all of this pans out, then you need to start looking for heat leaks in your system.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • RCO RCO @ 1:16 PM
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    Thanks

    Mark
    Thanks for your response to my question.  This is the course of action that I'm going to follow to try to rectify my heating issue.  I appreciate sites as this to help us, who know little about these systems, become more informed.  Also to try to steer a path that will try to resolve the current system issue rather than just add additional supplemental heating to fix the problem. 
    Thanks again!
    Ray
  • Greg Maxwell Greg Maxwell @ 6:37 PM
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    Rad heat issue

    We have run into this quite frequently, and although we dont use electric boilers, a btu is a btu, no matter how it is produced. My experience has taught me that there could be many possibilities for this.
    #1 Was the system sized properly. Was there a professional heat loss done for this property. Was there a radiant layout done? It is very possible that your system was never designed properly.
    #2 If so, was it installed per specs. I cant tell you how many times I have designed a system that needed supplemental heat, and have recommended panel rads to handle the supplemental load only to hear the contractor or homeowner say, I dont want that. Well, guess what? That job wont heat properly on the cold days if you dont address that issue. Period. If you need 10,000 btu in a given area, and your floor can only give you 7500, you will be having a problem. Slab insulation is another large problem, as you are ideally trying to heat the floor above, not the ground below. Adding or changing things during construction is another big problem. Was the cathedral part of the original plan? You mentioned that you have 1000 sq' with 2 loops. Does that mean that your slab is 1000 sq '? If so, you may have a flow issue, an you are supposed to limit your loop lengths to a max of 300', and at 1 lineal foot per sq foot, that would mean that your loops are too long, resulting in a larger than ideal delta T.
    #3 Operation. What is your water temperature? You will need to measure both supply & return temps. Are you using outdoor reset? Do you know what the floor temp is? Are there now rugs where there were none before? We look for an emmisive temp of around 87 degrees, although you can go to about 89 before you start to feel a notacible difference to the touch. 87-89 is where you are neither giving off heat to an object, nor is the object giving off heat to you. If there are rugs, and they werent initially figured into the plan, then you have basically covered up your heat emitters. You will not be able to get enough output. Do you have heat in the loft area? And, another biggie is your fooling with the thermostat. This isnt like the other baseboard hot water, or warm air systems, where you can turn it down when you leave, and turn it back up when you get home. Set it, and forget it is the best thing you can do for radiant. You may think you are saving, but in fact, its costing you much more. It takes a ton of energy to bring a mass like a slab up 10-15 degrees, and will result in a very unhappy homeowner.
    Solution. Find yourself a well recommended radiant heat contractor. Do a heat load calculation on your home, taking into account things like insulation, and floor coverings. Include your cathedral areas, and the loft area. When you have the results of that, compare it to the system you have now. Does the BTU loss match the output of the boiler for the coldest day? Does the BTU requirement per sq' equal your floor output ? If the boiler is large enough, and the slab is set up properly, it just could be an issue of adjustment. You may need to increase the water temp. Or, you may need to add supplemental heat. Although I would use hydronic panel radiators, not gas heaters. They are a good fit with radiant jobs, as they have a great radiant value to them. What I would recommend, is using 2 stage thermostats, leaving the slab on stage one, so as long as the slab can heat the space with no problem, so be it. Then, when the temps start to drop and the system cant maintain to +/- 1 degree, the rads would come on, and keep the space at the desired temp, until the radiant can take back over. Not a perfect solution, but one Ive seen many times.
    The final thing that I've seen on a lot of cottages, and beach house jobs, is that some were only sized for three season occupancy, and therefore wont heat during winter. No fun for the people that bought it. The panel radiator, 2 stage thermostat solution may be a good fix for that as well, providing you have enough boiler.
    Best of luck.
  • Leo_G Leo_G @ 10:55 PM
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    Ah, Thermolec

    boilers.

    RCO, how old is this boiler? I have about a dozen of them installed, and about ten of them have had similiar problems as yours. Every one of them had undersized electronic relays  for the elements. How do I know? Because every time I have ordered the new contactors to replace burnt out ones, Thermolec has sent out 25 Amp ones instead of the 15 amp originals.

    I think I read that the outdoor sensor has been disabled? If not remember that the max temp out from your boiler will be the same for -10*C as   minus 40*C. For some reason they decided that -10 is the lowest that was needed.

    Here is the PDF to their manual, it may help:

    http://www.thermolec.com/_documentationcache/cd-266-Boiler%20Manual%20Version%2011English%20Canada.pdf

    Also check to make sure that an inline timer has not been added to your system, if it has the temp drop could be from that.

    But my money is on undersized and burnt out relay or 2.

    PS - how much does the temp drop from daytime high to night time low in the winter?
    This post was edited by an admin on July 18, 2011 10:58 PM.
  • RCO RCO @ 11:53 AM
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    Thermolec

    Leo G
    This boiler was installed in 2009.  As I mentioned early on, we just purchased in December with the assumption that the boiler was functioning properly.  The temp will consistently drop 6 - 8 degrees at night time.  I'll make sure that the contractor checks the boiler for bad elements or other issues.  Thanks for your input.
    RCO
  • RCO RCO @ 11:53 AM
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    Thermolec

    Leo G
    This boiler was installed in 2009.  As I mentioned early on, we just purchased in December with the assumption that the boiler was functioning properly.  The temp will consistently drop 6 - 8 degrees at night time.  I'll make sure that the contractor checks the boiler for bad elements or other issues.  Thanks for your input.
    RCO
  • RCO RCO @ 11:54 AM
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    Thermolec

    Leo G
    This boiler was installed in 2009.  As I mentioned early on, we just purchased in December with the assumption that the boiler was functioning properly.  The temp will consistently drop 6 - 8 degrees at night time.  I'll make sure that the contractor checks the boiler for bad elements or other issues.  Thanks for your input.
    RCO
  • jonny88 jonny88 @ 9:47 AM
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    great thread,my stupid?

    the temp gauge on the boiler is saying 130 correct.i always assumed you wanted to make 180 degree water from boiler to prevent low water temp returning to boiler.then pipe into a mixing valve and pump out of mix valve to radiant zone.
  • Mark Eatherton Mark Eatherton @ 9:56 AM
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    Its an electric boiler....

    No flue gasses to condense, hence no minimum temperature of operation (within reason).

    It is 80 to 85% efficient fired (oil or gas or LP) appliances that need to be kept warmer to avoid the production of detrimental condensation.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • jonny88 jonny88 @ 11:40 AM
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    thanks ME

    THANKYOU AGAIN for your info,every day is a school day.
  • RCO RCO @ 9:59 PM
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    Resolution May Be Found for Our Heating Issue

    Hey Guys,
    After having a heating tech in to check out the boiler last Friday to find out it was working as it should, we believe we have found our problem.  The tech did a thorough examination of the boiler system and even called the technical person with the manufacturer to double check some things.  All was as it should be.  We again were told that we needed to look into a supplemental heat source.  But the tech spotted a controller on the outside of our house.  I told him that it couldn't be hooked up as we are paying the standard price and was told by the power company that we were not restricted. 
    We stopped at one of the electrical contractors in town to check out cove heat panels or baseboard panels.  We explained our situation to the estimator in the office.  He was perplexed as to why the system wouldn't keep the place up to temp.  I told him that early on I had noticed the set up for a 2nd meter so the plan must have been to go with a dual fuel heat at some point in time.  I then mentioned that the heating tech had noticed the control box on the outside of the house which I had not noticed prior.  This fellow said, "I bet you're being restricted on your heating electric and no one is aware of the situation!"(Except for possibly the heating contractor that is now living in Alaska!)   It certainly made sense to me as the off-peak time for the boiler to run would be 11 pm to 7 am.  The slab would finally heat up to start dissipating heat in the later am and then most heat would be gone by late afternoon.  System would be working overtime trying to keep the slab warm. 
    Well the power company checked out the controller today and sure enough that is what was happening!  We'll be anxious to see how the system works when fall arrives with colder temps.  Also curious to see how the bills will be.  I would have to believe that the cost would be somewhat less.  Once the slab is warm, the system will be able to keep it as such.  Will find out before too long.
    Thanks for all the advice and guidance!  I'll report back once the cold weather arrives.
    Ray
    This post was edited by an admin on August 14, 2011 7:26 AM.
  • Leo_G Leo_G @ 9:21 PM
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    WOW

    just WOW!

    Would never had thought of that one!
  • RCO RCO @ 8:12 PM
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    Saga Continues

    Well, I'm not happy to report back that I believe my heating woes still continue.  I don't think we've seen the drop in temp as we did last winter but it has dropped on some occasions.  We were up last Weds thru Sat and I noticed some fluctuation with the temp thru Saturday AM.  I picked up a digital Honeywell thermostat...just a basic model...that AM and installed.  The temp seemed to stay quite accurate through the night.  I turned it down to 60 when we left Sunday afternoon.  My neighbor checked on it Weds AM and it was spot on at 60.  So maybe the basic thermostat that was hooked up was suspect?? 
    Now, on Tuesday PM I checked my billing for the period of 10/24 - 11/26.  We used 1785 KWH for a total billing of $200 for that time frame.  I told me wife we couldn't afford to live there full-time if it was that much for just the short time frame we were there over that period!  We used around 115 KWH in Aug/Sept  and around 325 for Sept/Oct.  Also the fall has been quite mild in comparison to past years.  Of course, since I've only owned it since December last year, I don't have history to go off of for comparison. 
    I've a feeling that the system is either not adequate for the structure or we have a heat loss somewhere.  I'm not sure who to contact as the contractor's I've dealt with have just given opinions based on what was happening with the drop in temp rather than doing any actual calculations.  We know the boiler is working as it should but other things are pretty much an unknown to us.  I was hopeful that we would fix our temp drop problem (which may be the case).  But I wasn't counting on the usage to go up like it apparently has.
    Ray
  • Gordy Gordy @ 9:39 PM
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    Kilowatt rates

    What are they after all fees are added in?  I always figure the rate after fees.

    If you subtract 250 kw ( summer use)  from the bill. That leaves 1535 kw.

    1535kw  x 3412 btus per kw= 5,237,420 btus for the period. Its a guess as to how much heating you did in the period. How much occupied etc. But averaged out over the billing cycle 34 days thats 154042 btus per day or 6418 btus per hour, and 6.42 btus sf.

    Dont know the temps outside, or settings inside. What days were heating ETC.
    But thats a very ROUGH idea of the btus used for the heat on AVERAGE per day, and hour. If your other electrical appliances had same usage as summer billing.  I think your rates are very high like .11 cents per kw if total bill is correct.  Its hard to say with out degree day data, and actual heating usage.

    .11 cents a kw is not the highest in the country, but its not the lowest either. It will put a dent in the bill for sure.
    Gordy
    This post was edited by an admin on December 1, 2011 9:44 PM.
  • cattledog cattledog @ 2:19 AM
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    Benchmarking

    Welcome to the wonderful world of energy usage benchmarking, where you can record, analyse and obsess to your heart's delight.

    Gordy has pointed you in the right direction. First, you will need to separate the boiler kwh usage from the hot water, range, lights, etc. Summer bills are a good place to start but many of us get into more intensive monitoring. Second, you will need the Heating Degree Days (HDD) for your location.

    One standard benchmark for space heating is btus per year per square ft per HDD. (btu/yr/ft2/hdd).

    For moderately cold climates less than 5 btu/yr/ft2/hdd is doing well, but northern Minnesota may be on a different scale. Where under 5 is very good, over 25 is very bad. The benchmark is clearly dependent upon lifestyle, personal comfort zone, and wardrobe as well as the building envelope, solar gain, and the heating system. I don't know if you can get under 5 in Minnesota wearing t shirts and shorts all winter with the house at 75, but maybe someone on this site will come forward with a well insulated, high solar gain, case study.

    From Gordy's numbers and some hdd guesstimates I think you may be somewhere between 5 and10 btus/yr/ft2/hdd, but with the hdd data for the last billing period and for an average year, you can get a better estimate.
  • Gordy Gordy @ 6:29 AM
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    Found it

    http://www.kouba-cavallo.com/bnchmrk.htm

    I'm like cattledog a 5 btu a sf house in central illinois will not be a 5 btu sf house in the north.



    Gordy
  • RCO RCO @ 2:52 PM
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    Electric Usage

    Ok.  The usage was 1785 KWH @ $.0943 per KWH = $168.33.  The rest was standard service charge of $28 and tax.  We have a 955 sq ft of living space and home is 720 sq ft (30 x 26).  We were there 8 days out of this time frame.  I'll need to check on heating degree days but the zip for the area is 56470.  We had the temp at 55 for most of the time period when we weren';t there. 
  • Gordy Gordy @ 9:12 PM
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    living space

    Not adding up. 30x 26= 780. If there is a loft area it must be added in to the calculations you are heating it indirectly.
  • RCO RCO @ 6:29 AM
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    Wrong Dimensions

    Sorry Gordy......Should be 30 x 24....square footage is right at 720 for the main floor and 235 for the loft as indicated in previous message.  One thing I neglected to mention is that on 2 occasions for probably a total of 5 days we had the electric heater in the room above the garage on as well.  This heats the room quickly and is kept on low as it would sweat someone out of there!  The room above the garage is roughly 300 sq ft. 
  • RCO RCO @ 9:23 PM
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    More Information

    I haven't quite figured out the process for calculating the heat use.  I've provided info pertaining to the HDD per day for the billing period based on the inside temp for each of those days.  I've also included a breakdown of the monthly bill for the year by billing period showing number of days and KWH used. This is to give an idea of the KWH used during the months when the heat was turned off - May thru Sept.  The square footage of the main area of the cabin is 720 with 235 in the loft.  Floor to ceiling in the main area is 23 foot with 11 foot in the loft area and 9ft in the main area under the loft.
  • Gordy Gordy @ 11:42 PM
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    My take on the numbers

    6.2 Btus sf.  I was not far off. Average indoor temp for the period was 61 degrees. I used 127 KWH for a summer bill seemed to be more months in that area. Maybe no AC. Were you comfortable at 69* or trying to economize?

    I think a lot of the energy is bringing the slab in, and out of setback ,deep set back in your case. Your slab, and interior MRT just does not reach a steady state where the boiler can kind of coast a long, and maintain a temp. thus not using so much electricity.

    While 6.2 btus sf Sounds good it is a low indoor setting raise the temp another 8* to 69* heatloss goes up. even 10 Btus sf is not bad.

     I could be wrong, but I personally just think electric boilers, and waterheaters while 100% efficient just do not heat the water quickly like a gas style burner with a good HX design. I liken it to cooking on a gas verses electric stove. The energy is slower to react for electric.
    This post was edited by an admin on December 2, 2011 11:53 PM.
  • RCO RCO @ 8:10 AM
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    Supplemental Heat Source

    So, it may be the best thing to start looking at a supplemental heat source such as a gas heater.  That will allow us a discount on the electric usage on the heating system to around $.05 per KWH.  We have a wood burning fireplace but we like the option to use wood and also know the cost to convert that to a gas insert would be quite high.  The last heating contractor recommended electric panels to use as supplemental heat but that still keeps the rate up there for our usage.  Our issue is finding a good location for the gas heater.  What are the thoughts on vent free gas heaters?  My parents have had one in their home for several years without any issues.
    If I'm understanding correctly, we also may be better off leaving the temp set at around 69 evening when we aren't there??  I take it that we are using a good deal of energy bringing the slab from 55 - 60 up to the 69 setting.  It varied this last month as I was experimenting a little with the temp setting when we weren't there.  Up to this time frame, we had always turned the temp back to 55.  The 69 degree setting seems to be comfortable there.  That is where we keep our system at home which is forced air.  However, we do notice it is more chilly near the exterior walls/windows at night with the radiant heat.
    I guess in another month or so, I should be able to compare if we are actually gaining anything from last year with the heating system on 24 hours a day rather than the off peak last year.  I would guess if anything we should at least be able to maintain temp. 
  • Gordy Gordy @ 1:26 PM
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    Something to think about

    Your specific boiler is fully modulaing. At full output it costs 1.10 for every hour it runs. If it were an LP boiler at 2.85 a gallon nothing gained. If it were NG boiler Way cheaper but you do not have NG.

       Once your structure is up to the occupied temp setting your boiler can then modulate its output to the low end cutting operating costs.  Your longest stay is just 4 days at 69* set point. It can take that long just to get everything heated (slab, and all interior mass) to where the boiler can modulate down. Its worth a try before buying gas supplemental heat sources.
  • RCO RCO @ 10:34 AM
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    New Billing

    Just received our December billing for our cabin.  The usage was 1482 KWH for a total of $139.75 ($0943/KWH).  We were only there for 1 day of this billing period.  Again, all other days the thermostat was set a 55.  Of course we've had a very mild December in the upper Midwest so that makes a huge difference. 
    Although proibably not a fair comparison, I still have a hard time with the fact that our billing for November, 10/24 - 11/26 - of 1785 KWH @ $168.83. Our electric and NG usage at our home in eastern South Dakota was 1850 KWH @ $142.85 ($.0772/KWH) and $42.99 for NG for a total of $185.84.for a similar time frame for December.  We have a heat pump and NG force-air furnace.  Our home is an 1920-era home with not the best windows and probably inadequate insulation.  It is around 1500 square feet on two floors with another 750 in the finished, heated basement. We have a gas fireplace in the basement plus gas cook stove.  I realize the cost difference in KWH but still it is hard to see why they should be even as close as they are in costs.  I frequently check temps on the internet and they usually aren't that far off from our home to our place in MN. 
    I do believe that the new thermostat I installed is doing a better job of controlling the system.  I say this because we spent 3 days there after Christmas and the temp held steady all the time we were there.  I will do a comparison when we get our billing for December here at home which will be at the end of January. 
    Thanks!
    Ray
  • SWEI SWEI @ 11:45 AM
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    setback & control

    One day a month?  What about a remotely-accessible stat with deeper setback (like 40 or 45F)?  Do you have thermal drapes or blinds for those windows?  That will help when you're not there.

    Raise the space temp 3-4 days before you leave (or if the stat is smart enough, tell it what day and time you want the space ready and it will work out the rest.)
  • Jean-David Beyer Jean-David Beyer @ 1:47 PM
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    if the stat is smart enough

    My thermostats claim to be smart enough to start the heat early so as to hit the desired temperature at the time set. But they are not smart enough. The maximum mine seem to be able to start ahead is 90 minutes. Since one zone is a radiant slab, I need 8 to 24 hours advance to get the right temperature. Similarly, my baseboard has a lot of reset, so it takes up to 4 hours to recover from 4F of reset. The times when that adaptive recovery would really help are the times when it is pretty much useless. I no longer do any reset on the radiant slab zone, and I am still playing around with reset on the baseboard zone. I may cut the reset to 2F up there. I will know better once we get some really cold weather. It might go down to 16F Tuesday night. Design temperature here is 14F.
  • Gordy Gordy @ 1:50 PM
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    Nature of the beast

      SWEI I think part of the dilemma is recovery from set back to so the structure is comfortable upon arrival, and during their stay usually short periods.

       Doing a deep set back compounds this IMHO just judging from all the previous trouble shooting posts above.  Yes deep set back will save more energy during vacant periods, but it also will create higher energy use to get the structure up to stable temps for occupancy. This management is compounded when lower more realistic winter temps are realized.

      Couple this with an electric boiler that they have which is just sized to the design load, but undersized for  (pick up factor) in this case recovering the system out of a very deep setback.

      Learning T stats have their limitations as they are designed to sense room air temp, and not the MRT of the space. The MRT is the killer in this equation in that all the mass of the structure has to recover from deep setback.

      I think all that can be done in RSO's case is a lot of experimenting in which the most money can be saved with the least amount of sacrifice to comfort upon their arrival, and stay. Such is the nature of this beast. The only thing
     All I can say maybe  would be the edition of a supplemental pellet stove to cut the chill until the primary system can stabilize if a deep set back method is the road of choice.



    Gordy
    This post was edited by an admin on January 1, 2012 1:53 PM.
  • SWEI SWEI @ 2:20 PM
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    definitely possible

    That deeper setback could make things worse.  Or not.  I'd setup some kind of remote access (or at least try asking a neighbor to go over and turn up the temp several days before I arrived) and see what happens.  Surely Uponor or Tekmar makes something MRT-aware that can be remotely managed?

    Covering those windows, perhaps even doubling up or adding a reflective layer might make the difference whatever the control methodology.  Foil bubble may make a terrible general purpose insulation but it can work wonders over window openings, particularly when it's on the correct side (summer or winter) of another insulating layer like cellular shades or thermal curtains.
  • Gordy Gordy @ 2:43 PM
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    I agree

    With ya on all counts. I beleive the OP was having the neighbor turn the heat on in advance. Question is finding out the correct lead time, and temp.  Window treatments work wonders for insulating. Depending if windows could add solar gain with right orientation on property.............But then all is lost at night. Automatic temp sensitive control comes to mind for that.

    Gordy
  • RCO RCO @ 10:50 PM
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    Suggestions

    I appreciate all the comments.  Although the remote programming t-stat would be useful, as Gordy indicates, we do have a neighbor who is generally available to turn the stat up a day prior or day of our arrival.  Again, the time it takes to heat up the place isn't the issue that concerns us.  However, it is the perceived high amount of usage that is required to heat this dwelling when we aren't there much of the time.  Typically, we have used the place 3 to possibly 4 days in a month's time frame.  The November billing was somewhat of an exception as we were there the end of October, the middle of November, and over Thanksgiving for a total of around 10 days.  This current billing for December included from the reading on 11/26 - 12/26 in which we had been there from 11/23 to 11/27.  The heat was turned down to 55 degrees when we left on the 27th and we were not back up until after 12/26. 
    I have a hunch that leaving the t-stat set at a higher temp when we aren't there is probably going to cost us more due to the average days of usage during a month.  I have noted that the outer perimeter in the dwelling is cooler as we have an indoor/outdoor thermometer on the north wall.  That registers typically 64 or 65 degrees when the t-stat is set at 69.  However, the comfort level is OK in the place.  Gordy is probably correct in the assumption that the boiler is just big enough to heat the place.  Therefore, it might make the most sense in installing an LP gas supplement heat source to help.  Even if it wasn't used much, it would drop our KWH rate to .0552 from .0943.  The power company stresses that they would be able to control our heating electric up to 400 hours per heating season.  This is typically no more than 6 hours during the day.  As I told them, up to this season, we were being controlled 16 hours a day because we were on an off peak setup unintentionally. 
    Our biggest dilemma in a gas supplement is the space for installing such.  We really have no room on the main floor.  We have discussed the possibility of a gas insert for our fireplace but the payback on doing something like that would take years to achieve.  Plus the fact that we enjoy a real fire occasionally. 
    Anyway, we know that we have probably solved our issues with the temp drop.  First, by correcting the off-peak issue and then by installing a new t-stat  Unless we are being fooled by the more mild outdoor temps this year! 
    Bottom line is that we want to come up with the most efficient and cost effective way to heat the place during the winter season.  I believe possibly the only other option would be electric heat storage units which would qualify us for the off-peak rate of .044 per KWH.  I believe these units are quite spendy as well.  Again, the payback would take several years. 
    I'm thinking we should possibly look at a vent free wall heater for great efficiency, initial cost, and rate decrease for the best bang for the buck.  I know that there are a lot of mixed opinions on these units.  In our case, it would be something that would be used occasionaly....when electric is controlled and possibly to help bring out of setback.  We have been looking at blinds as well to help insulate the window openings. 
    Thanks! 
  • Gordy Gordy @ 1:46 AM
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    No gas fireplace

     The idea that a gas fireplace is going to heat could not be farther from this assumption. When installing a gas fireplace the damper must be open, or removed at all times. Guess what happens then.

    Gordy
  • SWEI SWEI @ 10:57 AM
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    storage heater

    Can you add a water storage tank to your existing system and qualify for the off-peak storage rate?  If so, you should be able to run the existing boiler (possibly adding a second in parallel) on a timer and shift your consumption to match their tariff.
  • cattledog cattledog @ 1:56 AM
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    What to do?

    Ray,

    You are making progress, focusing your concerns and narrowing down your options.

    The first thing to try is the deep setback when you are away. I think that the suggestion of setback to 45 is worth a try as long as you can get your neighbor to turn it up. I'd start by adding the same amount of time as it takes to go from 55 to 65. When you work the heat loss math, I think that deep set back and recovery will always take less energy, and with an electric boiler you don't need to worry about efficiency with how hard or easy it is working. But as mentioned there are comfort issues and the difference between the air temperature and the mean radiant temperature (MRT) of the entire mass.

    I can see that you are tempted by Minnesota Power's different rate plans. Since your are currently comfortable, but suffering from billing shock, the economic analysis and payback issues are key.

    If you go the dual fuel route, there are a couple of considerations. If you go for the propane wall units, I think that you will be much better off spending the extra money for a direct vented, modulating unit. I think that your house is too well sealed for a ventless unit, and the water vapor, oxygen depletion, and CO hazards are substantial. We want you to keep posting.
    Best, would be a true propane mod/con boiler tied into your existing radiant system.

    I think that the off peak power route also has merit, but you'll have to take a close look at your design day heat loss and the boiler capacity. Since you appear to be sized correctly, you may not have the capacity for significant storage.

    The easiest "all you gotta do" is convince MP to give you off peak rates when you are not in residence, and do a large daily swing with heating only from 11pm to 6am with the slab as your storage, and convert to the standard rate for the days you are at the house. This really would be a win/win for you and MP, but unfortunately it relies on the impossibility getting a large utility to do something special.
  • RCO RCO @ 8:09 PM
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    Fujitsu Mini Split System

    What are the opinions of these efficient systems that are available today?  I spoke with a homeowner across the lake from our place that had 2 of these installed last summer in his 2000 sq ft home.  He has been very pleased with the operation of them.  Of course, his purpose was to have a/c during the summer months.  But he has found that they have heated his home quite well this winter.  He said they are very low cost to operate.
    My thoughts are that one of these units could possibly help keep the radiant system from working as hard to get warmed to temp.  The bonus would be the a/x availablity in the summer months.  I've had 3 months of heating now and the electic bills have been $172, $142, and $173.  Again, we average about 3 - 4 days per month of use. 
    If we were up there more often, I think I would try to leave set at a higher constant temp.  I'm not sure if it would be worthwhile to do so when we are not there on a very regular basis. 
    Another question -  does it make sense to turn the water heater off when we aren't there?  I have been doing so each time as that was the practice.  I'm thinking that the water stays fairly warm as there doesn't seem to be much lag time once we are there and turn it back on. 
    We've also measured our windows for cellular blinds this past weekend while there.  We've resolved the holding temp issue as it will stay right at the setting we have it on now.  However, I do note that the temp by the outside wall is around 5 -6 degrees lower. 
    Anyway, please give opinions.

    Thanks!
  • Gordy Gordy @ 11:20 PM
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    Looking for AC

     I will comment on turning the water heater down. Beware that legionella will bloom, and the first shower you take after turning it back on will be loaded with that bacteria. see legionella thread on main wall.

    Gordy
  • cattledog cattledog @ 12:57 AM
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    low temperature performance of mini splits

    Ray--

    It's encouraging that your neighbor is getting satisfactory performance from his mini split. It's important to understand the low temperature performance of the system, and using them for heating in Minnesota is not the typical application. At low outdoor temperatures, the efficiency and possibly btuh will be lowered, but I think that a mini split will always be more efficient than directly converting electricity to heat. The outlet air temperature achieved at low outdoor temperatures is another issue. You may gain some additional efficiency, but blowing 65F air around the room may not make your feel warm.
  • RCO RCO @ 9:02 PM
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    I'm back!!!

    Hello, Still working on a solution to lower my heating costs. Just had a heat loss analysis done by electric coop from info I supplied. They came up with a heat loss of 33000 BTU. My boiler is 34000 BTU. So it seems possible that the boiler would need to run at its full potential to keep up. I was contemplating trying to find a gas heater to supplement to get the dual fuel rate. But I'm wondering if I shouldn't look into a gas boiler to work in conjunction with the existing electric?? This would allow for dual fuel rate as well as provide sufficient heat to the system?? Also could allow for future expansion for other radiant options? I realize this would be more costly but possibly a better option. Thanks! Ray
  • RCO RCO @ 9:02 PM
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    I'm back!!!

    Hello, Still working on a solution to lower my heating costs. Just had a heat loss analysis done by electric coop from info I supplied. They came up with a heat loss of 33000 BTU. My boiler is 34000 BTU. So it seems possible that the boiler would need to run at its full potential to keep up. I was contemplating trying to find a gas heater to supplement to get the dual fuel rate. But I'm wondering if I shouldn't look into a gas boiler to work in conjunction with the existing electric?? This would allow for dual fuel rate as well as provide sufficient heat to the system?? Also could allow for future expansion for other radiant options? I realize this would be more costly but possibly a better option. Thanks! Ray
  • Gordy Gordy @ 9:16 AM
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    Resolution

    I would go with a small mod/con period. You could use the thermolac for unoccupied periods to just keep the setback temp. Can't remember if you have ng or lp available.
  • RCO RCO @ 12:23 PM
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    Resolution Idea

    Hello.  I appologize for my ignorance but what is does is a mod/con? 
  • RCO RCO @ 12:24 PM
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    Resolution Idea

    Also, we only have availability to propane....no NG at this time as we are 11 miles out in the woods.
    Thanks!
  • Gordy Gordy @ 1:34 PM
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    Boiler type

    A mod/con is a modulating condensing boiler very efficient in the upper 90's. They are lp, or ng. They modulate their output to the demand.

    Only draw back is lp is not as stable as ng in pricing, but maybe some of the discount for dual may help.


    Gordy
    This post was edited by an admin on November 17, 2012 1:35 PM.
  • RCO RCO @ 7:57 PM
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    Clarification

    Thank you for the clarification.  What size do they typically come in BTU's?  Would I look at something similar in size to the existing electric boiler?  Do you have a ballpark as to the cost of such?  I'm guessing I wouldn't use that much gas as typically we'd rely on the electric unit.  We would cut our electric rate from $.0943 per KWH down to .0552 per KWH on a dual fuel rate.  I believe I've pretty much the set up for the control of the heat.  Electric coop just needs to install the 2nd meter which the housing is already there.  They will return the control unit for the controlling of the electric boiler.  Does the propane unit need to be mounted on an exterior wall?  That may be my only issue as the utility closet has access to an outside wall.  However, the wall is under the landing of the stairway and the water tank/pump are in front of it.
    Thanks!
  • NYplumber NYplumber @ 10:40 PM
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    Free standing

    Try looking at installing free standing large cast iron radiators to warm the space up quicker till the radiant catches up. Cast iron also holds its temp for long, so the boiler may not run often for it to keep.comfortable.
    :NYplumber:
  • AFred AFred @ 10:04 PM
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    Depends on your plans

    Is this going to be your retirement home? Are you planning on staying year round?
    I think the best idea might be an LP boiler. You could look into heat pump mini-splits, then you'll have air too. They will heat down to -5*. It will get colder than that up there tho.
    Heres a few pics, these are located near Bemidji (not year round, but close).
  • RCO RCO @ 1:38 PM
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    Feedback

    Thanks for the feedback on the radiators and mini-split system.  I've actually seriously looked into the mini-split.  But the majority of people I have spoken with that have them do so mainly for the A/C factor.  If it was a seasonal usage place, that would be OK as well for some efficient heating.  However, I don't think it will help us in the cold months of December - February. 
    Our main objective is to cut heating costs (electric) to a dual fuel rate.  I believe that is my best alternative to be able to go from $.0943 per KWH down to $.0552 per KWH on our electric boiler heat. 
    After having a heat loss analysis done, I'm thinking that maybe we need more than just a gas supplement heater to get the reduced rate.  Maybe it makes sense to go with the gas boiler to help keep the system running as efficient as possible.  As mentioned earlier, I have a 34,000 BTU electric boiler with a 3 loop hydronic system in the concrete slab.  We don't have an issue with keeping the place up to temp while we are there.  But for the amount of time we are there and using it, it seems to cost too much to heat.  Therefore, the reason to get on a dual rate.  The heat loss analysis done, which is as accurate as the info I gave the electric cooperative that completed it (see attached).
    Does it make sense that a propane boiler would help supplement the electric boiler?  Or are we going to have overkill with the 2nd boiler and spend more $$ than it is worth?  I know the heating loops will only but out so much heat (or as much as the body can tolerate).  I would guess we could possibly add on radiant heat panels down the road if we want with the 2nd boiler system?? 
    Again, still looking for the best alternative to come up with the most efficient and cost effective avenue.  My original thought was to go with a vent-free gas heater (inexpensive to install) but possible issues with moisture and health hazards from different discussions I've had.  Installing a direct-vent heater would bring the cost up quite a bit.  So due to the fact of limited space available for a heater and cost of such, it has made me think about the propane boiler. 
    We do not get any rate decrease for off peak with a mini-split system and we would need to have a ducted heat system to use a standard heat pump for that break according to our electric coop. 
    Thanks for the suggestions!
    Ray
  • Gordy Gordy @ 9:49 PM
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    High heat loss

    46 btus a square foot is pretty high. Your only going to get 35 btus a square foot out of the floor radiant, so you need supplemental. Your walking the line with the boiler you have being only 34000 btus.


    You pretty much only have a few options.

    Get a mod/con properly sized, and ditch the electric boiler on eBay., and add some rads.

    Use both boilers with the electric for setback while gone, and the lp for occupancy. Pray lp market is stable.


    Keep things like they are Bite the bullet with the present boiler, and add some supplemental rads see if that helps in the heating. Add the lp boiler later if extra emitters don't drop the electric bill. Either way you could use more emitter to help heat, add the gas boiler as a last ditch effort to drop your rates. This way you could do it in stages. Least expensive first with the emitters panel radiators can be elegant, and space saving.
  • Jeffrey_Bruton Jeffrey_Bruton @ 1:38 AM
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    Best Thread Ever! :-)

    Ray, Gordy, et al:

    What a wonderful, nearly year long, thread!  I miss Mark's post however!  :-(

    Our company in Washington State is a residential builder.  We build spec homes using Insulated Concrete Forms...and the homes include radiant floor heat in a slab on grade.  Not average for our area.  But since I'm the boss and I think crawl spaces are evil, that is what we do.  :-)

    One thing I always mention to perspective buyers and those who are interested in what we're doing is that radiant floor heat (IMHO) is rarely going to be the least expensive heating option.  With that said however I believe it is the most comfortable type of heat for human occupants...and possibly the best in regards to IAQ (indoor air quality).

    In reading the thread tonight (and thoroughly enjoying it) and looking at the pics Ray has posted, I would suggest that his vacation cottage looks very nice, i.e. high end, for which he is fortunate indeed.  Growing up in Eastern Washington, when we said we were "going up to the cabin"...it REALLY was a cabin!  What I mean by mentioning this is, typically in a high end residence (irrespective of size in sq. ft.) comfort and occupant experience is of more importance than low cost of ownership.  I don't know if Ray has talked to the original owner regarding this but I would bet that lowest cost of ownership was not the first goal when designing and building the cottage.  Just my supposition.  With that in mind however, once the utility's control device that should NOT have been in use was disabled, and he installed what seems to be a way better functioning tstat, I think the system is working well, i.e. as designed.  Not inexpensive, but well and as designed.

    From my admittedly limited knowledge of radiant floor systems (and further limited by all we do is radiant floor in slab on grade) I put forth that in the cold parts of our great nation, one layer of 2.5 inch EPS or XPS foam board under the slab is fine to make it work well, but not nearly enough to make it the type of cost effective heating solution that Ray and countless other owner are looking for.  We need to start following our "net zero" pioneer brothers and sisters by ALWAYS putting multiple layers under the slab.  R-30 should be a minimum with R-45 and R-60 the norm in places like his locale in northern MN.  The cost increase on a modest sized residence would be approx $500 to $2k during construction, but would make the home more comfortable to live in and make the radiant system perform, cost-wise, MUCH more in line with the typical desires of the owner over the life of the structure.  This of course assumes that proper foundation insulation, and better yet "frost-free" horizontal insulation out from the foundation options as detailed previously in this thread are also incorporated.

    With that said, I STRONGLY urge Ray NOT to install a ventless gas heating appliance of any sort...if he likes the people who will be in the building during it's use that is!  :-)  Installing a second boiler running on LPG would indeed cut his power cost per KWH nearly in half...and give his system more goose re: bringing the slab back from setback. With that said however remember that the "P" in LPG stands for "petroleum"...or in other words "oil".  If the goal going forward (over hopefully many years) is controlling heating costs, adding a component that runs on fuel made from oil might not turn out so well.  :-)

    My personal solution would probably be:
    Add the LPG boiler.  Granted I say this since I can do the work and the only cost would be materials.  This would drop the KWH cost nearly in half and provide the other benefits mentioned above. In addition it would provide something I personally ALWAYS include in designs but have not heard here: provide for backup in case THERE IS NO POWER!  Granted, fully implemented, this option would include a battery powered tstat and a UPS for the pump...but those two things are relatively inexpensive.  I actually always spec a gas fireplace so if the power is out (and in this case the UPS for the pump runs out before the power comes back on) we still have heat.  Granted this doesn't cover you if the power is out for a LONG time when you are not there and the power of the UPS runs out.   It does cover you however if you are there and can fire up the portable generator in the shed.  Also, since of course the outside BBQ is also fed off the LPG tank, there is full blown cooking even when there is no power.  And by the way, it tastes WAY better when everything else is going sideways due to no power but there is still a hot meal!!

    I realize that a real fire is often more desirable than a gas fire, but not having to get out bed when the power is out to put more fuel on the fire in the middle of the night makes big points with the wife.  Also we are trying to be covered when the power goes out in the middle of the winter and we are not there.  PEX tubing in the slab (and elsewhere in the residence for that matter) is indeed forgiving re: freeze/thaw compared to other plumbing options...but I would prefer to not press my luck.

    Many, many thanks to Ray for posting his initial query and to all you great folks for making it one of the best threads I've read anywhere, on any topic!  MUCH apologies for the very long winded post!!

    Thanks
    Jeffrey Bruton
  • Jeffrey_Bruton Jeffrey_Bruton @ 2:01 AM
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    Still Covered!

    It's so late that I forgot....our newest home (like our last one too) is fine even if the power is out for a very long time.  There is a separate t-stat for the fireplace which runs off batteries...and the wonderful little Lopi Northfield LPG gas stove has either normal free standing pilot (on all the time) or electronic start pilot which is battery powered...so you are covered for as long...well...as big as your gas tank and the batteries I guess.  :-)
  • Jeffrey_Bruton Jeffrey_Bruton @ 11:27 PM
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    Forgot that...

    Lying in bed last night I remembered a UPS for the pump, battery t-stat, and full propane tank are not enough.  You still would need a back up power source for the electronics in the boiler or the zone control panel, whichever your t-stat connects to.

    I remembered this is why I always provide back-up heating via the LPG fireplace/stove and battery t-stat...which provides automatic, unattended, back up heat for a very long time.

    Maybe no more posts late at night, eh?  :-)
  • RCO RCO @ 5:47 PM
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    Electric heater

    What are the thoughts of using a suspended electric heater to help supplement the existing system. It would assist in helping the radiant system keep up and also help with quick heat up of the place??? We have one in the room above our garage up there which we use occasionally. It warms up fast and has to be on low to keep from getting too warm. Are these available with a separate thermostat from the unit to control more precisely? I was thinking that it would be a fairly inexpensive addition and may help conserve electric usage from the boiler standpoint??

    Thanks,

    Ray
  • SWEI SWEI @ 8:56 PM
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    suspended electric heater

    Something akin to a radiant trough?  That would quickly make the space comfortable.  Wire it to a suitable TRIAC thermostat (think Aube/Honeywell) set a couple of degrees below the main stat and you should be good to go.

    What size is your electric service?
  • RCO RCO @ 9:56 PM
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    Suspended Electric Heater

    These are the electric or gas units that are attached to the ceiling, typically in a garage or shop.  My wife doesn't think the one in our 14 x 26 room about the garage is too bad looking.....light tan color.  They heat up quickly.  It's not going to give me a break in the electric rate but would possibly help the infloor system from working hard to keep up??  Going with the propane unit would give me about a 40% discount in rate for electric heat.  The unknown is the cost of propane to heat when electric is controlled or to help supplement the electric system.  Also the cost of the direct vent heater, etc. is going to be a considerable amount to install.  These electric units are relatively inexpensive to purchase.  Just don't know how much it will help lower cost of KWH??
    Thanks!
    Ray
  • animatt animatt @ 11:06 AM
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    questions and things to consider

    Have you tried to turn temps down further when you are not there. Rather than just 55f.

    You are heating the house weather you are there or not. It appears your electric bill is not to much affected by your visits as they are fairly short. That means you have several solutions to bring costs down. They fall under 2 categories.

    1 get cheaper electricity. Definitely a viable option but no guarantee where rates will be later. Seems to be the low hanging fruit.

    2. Use less electricity.
    a. Do not heat house as much when you are not there. It appear from the document attached that January had temps averaging about 0F .
    If you could change set back from 55F to say 50F you could save a good bit.
    I will use 55F as standard and compare what heat loss should be as a percentage.
    70F = (70F-55F) /55 = roughly 27% increase in heat loss.
    60F= (60-55)/55= roughly 9 increase in heat loss vs 55 degree
    50F= 50-55/55= roughly 9 percent drop in heat loss.
    45F= 45-55/55= Roughly 16 percent drop in heat loss.
    40F= 40-55/55= roughly 27 drop in heat loss.
    35F=35-55/55= roughly 36 percent drop in heat loss

    you get the idea. I think some saving could be had but just setting thermostat down a bit further when you are not there. It seems you are far away and visits are not spontaneous so you could have the heat turned on maybe 4 days in advance. Your heat loss drops when inside temps do as well so house should be fine. Heat loss Calcs were probably done assuming inside temp of 70F. Well heat loss at 45F are roughly 36% of what they are when at 70. So heat loss number of 34000 becomes 21k-22k

    b. More Efficiently heat the space. This can be done many ways. But your current system is getting less than 1 cop.
    http://www.businessdictionary.com/definition/coefficient-of-performance-COP.html

    Your electric boiler will run at 1 cop but the entire systems with pump and everything will bring that down to under 1 cop.

    You were talking about a mini split. Seems like a good idea to me although it should only be used to supplement due to your weather. I would make sure it was one that did not have an electric heating element in the outdoor unit. Some units to make sure they perform when outside weather gets cold have an electric heater in the outside unit. Kills efficiency. Anyway efficiency will be much lower when it is around 0F. But at times when the outside is in the teen and up, your COP should be above 2 and in shoulder months it should be probably higher than 3 cop but depend HIGHLY on unit. Not all units will work in the cold. Maybe a centrally located single 18000 btu unit would help the floor a lot. IN shoulder months this should drop electric usage a lot. Maybe in half. Weather of not that will payback fast enough is another issue.

    b. Heat more efficiently by reducing the need to heat. Better seal the house. I know it is not glamorous at all, but simple air sealing by owner diy has incredibly fast payback. Basically any air that infiltrating the house bypass any insulation and diminishes it value.
    It would be like filling a bowl with water that had a few small holes in its bottom. As long as the facet is on the bowl would be filling with water. But as soon as the facet is shut off, the bowl empties in short order. Even if the bowl had walls 1 foot thick the wholes with bypass and escape quickly.

    I would take an infra red heat sensing gun and check all around the house. Big culprits are windows and doors, and recessed lighting and outlet boxes on the walls.

    Basically go around with the gun and check near a recess light, then on the light unit. Obviously light is turned off to not heat the area. You could be surprised. A few feet away maybe 60F and you get to the light and it is 35F or lower. You do this for anything coming into the room from the walls. Windows will read lower, but it should be fairly even all around a window, if not there is an air leak.

    Now document your problems if there are any, which there probably is. Now go about solving the issues. Afterwards you will lose less heat. This will save you money all the time, what ever fuel source, it does not wear out, it is there for the life of the house. It is not flashy but has a great return on investment. Probably not what you want to do while visiting the house, but it really is not a mansion so not so long. Maybe identify problems one trip and next trip solve them.

    Anything that can reduce heat loss will make current and future work less. I read somewhere although I do not know the validity of the statement but was. The AVERAGE US house has an air infiltration equivalent of have a door wide open. Probably not your case as the structure is small. But most people dismiss small leaks of air, but would close and outside door pretty quickly. Small air leaks add up quickly.

    To address your last post.
    I myself would not throw and electric heater in the house that had a cop over 1 or less.

    Also something to think about with propane, and I think another post already mentioned it. It can be of great assistance if power goes not there. Not sure your intentions at the property. I mean if power goes out there, you could just end trip and go home etc. But a propane heater works with little electricity. What would happen at your house if electricity went out for a week? Water lines in the walls? Water in the toilets, etc.

    This brings me to my last comment and this one would save you money quickly although some things to think about before implementing. How about short term winterization. Have fluid in heating system be antifreeze. If it is easy to drain all water line in the house. Depending on how house was built it maybe very easy.

    Basically shut house down when you are not there, and 5 days before a visit have neighbor turn heating up. For the first 2 days the house heat loss would be very small, and things would heat up very quickly. Once the house starting heating up recovery rate would slow down. There are many things to investigate with this method before implementing.

    Just some thoughts. It seems turning thermostat to 45F would be a quick solution to start lower usage.

    Sorry for any typos. It is Christmas and have to get going.

    matthew
  • Gordy Gordy @ 12:02 PM
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    Mathew

    Have you absorbed the whole thread? Part of the initial problems were inability to maintain set point, and high operating costs.

    With those two issues in mind, and RFH as the emitter with an electric boiler that is right to the limit in sizing to the heat loss of the dwelling no emitters on second floor.


    The more you setback the longer it takes to get the dwelling to set point for the times of occupancy. Yes you will save more in unoccupied periods, but it will take more time to get the dwelling to temp for occupancy. If there is a power outage the lower the set point the less time you may have to deal with an unwinterized cabin.

    Even when heating with propane the boiler is electricity dependent.

    Personally I think window treatments on all glass would dramatically improve heat loss alone. Lots facing north.

    A pellet stove may be an alternative supplemental heat source during occupancy also providing convection heat to the upstairs. The existing fireplace is prefab with stone veneer over framed chase. That stone veneer is a lot of mass that sucks from the MRT in the room for quite some time. You can buy pellet stove inserts that resemble a fireplace which may swap out with existing prefab. You would have to vent it through the wall in the back of the chase you already have a fresh air intake for the existing prefab fireplace.


    The way this thread is going the OP wants the lowest cost solution possible, and the lowest electric bill possible.
    This post was edited by an admin on December 25, 2012 12:31 PM.
  • animatt animatt @ 2:45 PM
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    Yes I read it all

    At lower temps heat loss is lower. Raising it from 45f to 55f with current boiler would not be an issue as heat loss will be much lower. The problem comes from raising it the last bit as heat losses are getting higher and closer to the limit of the system. So if the house is already at 55f and has little issue getting to a reasonable temp going to 45F just means starting heating earlier. With the amount of empty time house has it would save money overall.

    While am an not a pro, it is simple math, and investigating abnormal heat losses.
    I find most people do not want to have good quality window treatments, although alot of heat savings can be done there. I say good, goes beyond a simple window shade that does not seal the air cavity between it and the window. Say the walls are supposed R-19 forgetting thermal bridging etc. Windows are an R2 maybe R3. With good window coverings you could bring that way up. Cutting losses from windows down dramatically, baring air infiltration problems. So I do agree. It would be a good way to reduce heat demands.

    But deep set back is not a big issue. Thermal mass can only store so much heat or lack of(cold). So even if the house was at 0F it would take a certain period to heat up. From 0 to 30F would happen much quicker than 30f to 60F. Boiler efficiency would be the same but not the houses. Heat loss calcs are house at temp, not at 45F. So heat loss is way down when temp goes down. Simple math.

    It would require a longer time to heat up, but the overall saving would be there. I can guarantee it especially since we are talking electric boiler with a fixed efficiency.

    You are correct about the power going out and starting with lower temps and quicker freezing. Fairly easy to make a backup system for a propane boiler. A small 1000 watt generator would be more than enough, or a few deep cell batteries, alpha circ pump would help as well.


    I am sure that fireplace stone is taking alot of time to heat up. Old house I lived in had something similar in size. A bit wider but a bit shorter, but was built will full stone, not veneer. I used to have that space set at 50F when not in use. Using baseboard radiators. When I turned on thermostat it would take maybe 12 hours to get up to temp. There are alot of variable, but it does have alot of thermal mass, much more so than any other single component of the house baring the slab.

    Another issue that deals with comfort and not cost would be to turn up temps in the day time to charge the slab more. You could have temps in house maybe go to 74F, and night it would still drop down a bit, but you would start higher, although the drop in temp to say 67F would probably not feel so good after being at 74F. Also it would cost more to do it that way. Another variation could be have thermostat set to 70F during day and at 3pm turn it up to 74f. It should start ramping up slab temps but really not effect space temps much.

    And yes I read the whole thread. Getting cost lower by getting electric rate less seems more accounting type of solution and while it works I am more into lower heat losses as well, as it is less dependent on a electric rate that could change at any time.


    Unless builder paid extra special attention to air sealing the house there is alot of air infiltration that can be tackled. I personally believe the radiant slab hides the drafty nature of certain houses. So heat loss is similar with a baseboard system, but different air flows.

    One question what does outdoor reset accomplish on a slab. I see there being little value to modulate water temps in the slab if boiler efficiency is always the same. Seems better to use higher temp fluids and pulse/(turn on and off for certain periods of time) the circulator to safe pumping power.

    Will the outdoor reset start the heating system if house is to temp, but outside is dropping in temps? Did not understand if the outdoor reset is now working or not. Seems like only useful if slab sensor was used in the controls so even if room is to temp the slab sensor would start heating before slab temps start to fall drastically. I suspect and just really a guess that house is getting to temp in early afternoon. and system shuts off. The mass in the floor is keeping room temps up for a while, but then slab temps start to drop fast and the marginal heating system has to fight a slab that is already dropping in temps. Really easy to test. Say at 2pm turn heat to 75F and see what happens during the night. This is eliminate any slab cooling period. While it will use more electricity, it will tell if added controls would help with the comfort aspect.
  • animatt animatt @ 3:03 PM
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    heat loss for OP

    I think I can present heat loss numbers a bit better.

    Now based on 70F as baseline. And averaging ambient outside 0F over entire month.

    55F setback has heat loss 55/70 =78.5% as 70F. So whether you are there or not your are heat that house alot.

    45F setback 45/70 = 64% as 70F.

    You being at the house 4 days a month(70F) is the equivalent of 5 days unoccupied at 55F.

    I think OP does not realize how much he is heating if he is there or not.
    Another way to look at it is if bill is $180 for the month unoccupied. Occupied would be around $230. To me does not sound tremendous considering he is using an electric boiler. So op is saving $50 doing the setback roughly. Maybe more with air infiltration and other misc.
    Ambient temps are brutal there.

    Try to lower demand, and getting a lower electric rate would help.
    This post was edited by an admin on December 25, 2012 3:14 PM.
  • SWEI SWEI @ 3:19 PM
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    outdoor reset and slab heat

    were made for each other, which most of us understand quite well.  Have you ever lived with a high mass floor running bang-bang on a conventional boiler?  The over- and under-shoot can be maddeningly uncomfortable -- and it burns far too much energy.  Properly commissioned outdoor reset produces superior comfort and efficiency.

    Window coverings have been suggested and may already be in place.

    We have suggested using the existing electric boiler to keep the space at a stable, low temperature all season.  Augmenting with overhead radiant will get the space comfortable quickly while the slab heat catches up to the desired occupied temperature.  Adding thermal storage to take advantage of baseload rates or conversion to LPG are options that need to be explored.
  • Gordy Gordy @ 3:38 PM
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    Mathew

    Most new boilers do not operate on generator power especially small generators (dirty power supply). As has been seen here on the wall from hurricane sandy casualties.


    I believe the op has the info needed, and now is trying to intelligently figure out best cost effective options. AC is part of this that's where min splits play into the picture.


    I applaud the op for taking the time to approach options in an intelligent manor, and not throw money at the problem.
  • animatt animatt @ 5:34 PM
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    matthew

    Depending on what small generator. There are some horrible ones, but also some very good ones, atleast how I understand it.
    Cheap chinese knock off probably not very good choice. It could be a bit of money for a good one. (Not a home depot special) The idea of a small generator is not to be cheap and save money on purchase. It is to be very portable, and usually lower noise levels and also lower running costs if your base load is only 500watts. Running a 5000 watt generator may work for a whole house solution if you want to run lots of loads, but for running 8 hours at night a small generator with lower noise would be my preference.
    I have lived in off grid house in warmer weather location. Adding a 10 gallon tank to a small generator could run for a long time, or even a lp generator. Since it is a vacation property have a gas line plumbed to outside with inside shutoff. In case of need just carry small generator to location and connect. But really that is a whole other can of worms, or should generator be permanently mounted and fire automatically etc. Generator really not part of this post but somewhat easily achievable.


    As for outside reset in this situation. Not sure that is contributing anything without a floor sensor? I think outdoor reset works better when you have a heat source that is sized with a bit more margin of heating capacity. This way it can crank up and heat the slab somewhat faster, or adjust for large swings in temp. But with a marginal sized heat source just not seeing the great benefit. It seems over shooting in the early evening would be beneficial here.
    A sensor to monitor slab temps and make heating decisions seems better fit in this case.
    Rather than modulate water temp.

    I have never actually worked with the outdoor reset though. Fortunate to do staple up installs on several low mass wood floors. Much faster response time. And even a sandwich type similar to warm board.

    As for window coverings I not sure if OP considers the shades he has to be them. While better than none, far short of what is available. Also the odd shaped windows by sides of fire place is a little harder.
    http://www.builditsolar.com/Projects/Conservation/MylarStorms.htm
    http://www.builditsolar.com/Projects/Conservation/bubblewrap.htm
    http://www.builditsolar.com/Projects/Conservation/Astrofoil/AstrofoilShutters.htm


    Mylar storms seem like they could be left all the time. Of atleast on the high windows. Low windows and doors could have the bubble wrap installed in a few minutes before you leave the house. Although some people do not like the effort involved, but it would cut heating losses a bit.
    May want to check out builditsolar.com specifically the conservation section has alot of things that may help you.

    Matthew
  • Gordy Gordy @ 7:08 PM
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    Mathew

    My charger for porter cable battery tools will not work even in high quality Honda, ranger type welder generators dirty power symbol flashes
  • SWEI SWEI @ 12:40 AM
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    indoor and outdoor reset

    The point of outdoor reset is to deliver the amount of heat needed to offset the envelope losses for any given outdoor temperature.  Combining this with an indoor thermostat (acting as a high limit control) will produce better comfort and efficiency than most Americans have ever experienced.  Really.

    Slab sensors and indoor air temp sensors wired to a top-of-the line control can
    make further improvements by dynamically adjusting the reset curve.  I wouldn't even think of throwing out 95% of the benefits of outdoor reset just because I didn't get the latest 5% of possible refinements with it.
  • animatt animatt @ 2:17 AM
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    comments and questions

    I believe the boiler can supply 35000 btus . Without floor sensor.
    Say it is 15F during day time, and -10F at night.

    Say at 70F interior temp house is losing 28000 btus during the day. That would make night time heat loss roughly 41000 btus.
    I know just guesses really, but I think something that is happening in this system maybe different numbers. Day time heat loss is lower than boiler can supply while cold nights brings heat loss higher than it can provide.


    Would it not be better to precharge the slab during hours of extra capacity to prepare for when the heating system can keep up. From a comfort aspect seems like a winning situation. Will not save any money though. Still would be better to reduce heat loss so night time losses could be handled without buffering heat into slab.
    It was suggested that thermal tank could be used to take advantage of base load rates. It could also be used to add heat to the system while boiler is being under utilized to be released at night when boiler can not keep up, But op said not much space. Not sure what not much space is? Thermal tank could be built really easy although I would venture to guess most here would buy a tank. If used electric tanks could be bought for cheap would be something to think about.
    Not sure max temp boiler can supply.
    2 -50 gallon tanks water raised to 130F(even higher better) say provide useful heat maybe down to 110F. Would only store an extra ~16k btus. If storage could be gotten higher to say 150F ~33k btu. That should cover extra heating needs, If water temps could not get so high adjust water volume would be useful, I personal am a fan of onsite built tanks, as they can be custom made to fit the space available. I would think for less than $300(material costs) a custom tank of 200 gallons could be built but depends on tank geometry. I built a 1200 gallon tank in a basement for no more than $2000 and that has 3 large heat exchanger(r50 insulation). Anyway this comment is getting away from me. I start typing and my mind starts wondering onto different possibilities although probably more non traditional from what most on here go after.

    Trying to get back on track to really wanted to ask about is the out door reset.



    I am really curious on how a out door reset would handle the situation in this case with boiler on the boarder of its limits(assuming there was floor sensor). I am not doubting out door resets in general. I am just thinking in this case with limited boiler it makes little sense to throttle the boiler back.

    Does the outdoor reset learn it can not keep up with heating demands? How does that work. Is there a forecast based model that predict on future weather. It seems in this system if you did not predict ahead it is not strong enough to keep the system at desired temps.

    Not doubting out door reset, just its usefulness in this case, especially mid winter weather. Shoulder months could be a different story.

    Matthew
  • Gordy Gordy @ 6:41 AM
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    In aunt shell

    You are burning more electricity than needed either by charging storage tanks, or heating the slab more than it needs to be. This is all using more electricity which the op is trying to get away from.


    Well designed radiant systems provide comfort. Adding a fly wheel effect to the slab by over heating during the day voids this.


    The bottom line is the boiler size is so marginal to the heat loss that it struggles with deep setbacks the deeper the worse it gets. With that said for a weeks stay the house needs a few days head start to catch up,so to speak. For those few days its running flat out to get the mrt of the structure up to temp.


    To lower the electric utility they need more emitter, and a slightly larger heat source of another fuel type....lp but that can be a crap shoot in today's markets. Plus the op wants to take advantage of the dual fuel special electric rate. Plus ac ability.

    Ac options are window shakers, or mini split

    Mini splits do not fair well for heating at low temps say 5*.


    Pellet stove could help with heating dramatically especially if neighbor is willing to fire up the day before arrival. Plus the use little electricity, and will run on dirty power in an outage.

    Ac honestly I would opt for a,couple of window shakers for their climate region.
  • RCO RCO @ 9:33 AM
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    Back Again!

    OK.  After our largest electric bill ever....$333 for the month of January....we are forced to do something here!  We used 2877 KWH for 31 days in which we were only there for 3 days at the end of the month.  We are looking at a price increase in rates as well but don't know exactly what they will be at this point.  Part of the $333 was a power adjustment of $31. 
    We are looking at a gas direct vent unit that will fit the minimal wall space we have available which is basically on the stairway landing about 5 ft up.  We've researched many units but haven't found one that will work that is at least 80% efficient.  Any ideas out there for vented heaters?  We do have 2 ceiling fans - 1 in loft and 1 in main area of cabin.  We can run those to help push the heat down. 
    Thanks!
  • SWEI SWEI @ 9:47 AM
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    gas direct vent

    http://www.rinnai.us/direct-vent-wall-furnace is probably worth a look.
  • Gordy Gordy @ 11:36 AM
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    KWH

    That's 11.6 cents a KWH about the rate here in ill. Not the highest in the country by far, but expensive.

    You really need to ditch that electric boiler, if your are going to see any real utility reduction. The gas heater is kind of a bandaid in my opinion. Money spent that could go towards the new boiler.
  • SWEI SWEI @ 11:41 AM
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    LPG boiler

    Put a PTS60 or a WHN055 in there and stop worrying.  Much better investment, and with those electric bills it should pay back pretty quickly. 
  • RCO RCO @ 12:11 PM
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    Gas Boiler

    I guess I can see the gas boiler as an option if we were going to add more radiant options other than the floor.  But is a gas boiler of 40,000 or 50,000 going to put out anymore heat than our current system?  I believe we are still going to get only as much heat out of the floor as there are corresponding loop lengths. 
    We had a contractor out to the place last Thursday while we were there.  They wanted to slap a 80,000 BTU gas boiler in for $5000.  However, they said they would turn the temp on the system up to get a little more heat out of the floor.  But it still isn't going to heat sufficiently unless we bring more radiant units off that boiler at higher costs yet.  It would be more cost effective at this point based on current prices of LP vs the general service cost per KWH.  But it seems to me it would take a long time to pay for this upgrade in the amount of savings we would get. 
    With a dual fuel rate, we start saving instantly by a $.04 drop in electric rate.  I'm by no means an expert but have done a lot of research.  I just can't see the conversion to an LP boiler without adding more radiant panels around the place to help.  I also believe we don't have the adequate space for a backup LP boiler to go that route either which is something I've considered.
    Thanks guys for the ideas!  I have learned a lot through this process.
  • Gordy Gordy @ 12:27 PM
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    confused

    Yes you are under radiated somewhat, but the goal here is to reduce your electrical consumption is it not?

    Your bill reflects an average of 13200 btus an hour in a 24 hour period for the billing cycle. This is a very rough estimate if nothing else but the boiler is using electricity which we know there are other draws on power. So your boiler is using less than that, and more depending on the load at the time.

    I think 80,000 btus is way to much. Like SWEI says go with TT 60 or a Knight 50. It gives you room to add some baseboard in the future.

    You keep boasting these dual fuel rates. just throwing a wall furnace in to get the reward seems like a bandaid to me. If your going to do that may as well ditch the radiant all together. save the electricity.

    Really dont know what to say I think you have researched this, and have been given plenty of opinions, and advice its time to make a choice. Nothing is concrete in utility rates no matter which way you go. Its to bad you do not have NG. But it could happen in the future.

    By the way are you SURE no one is living there while you are away? thats a lot of KWH for only being there for 3 days in a month. My usage was 2029 KWH for a family of four at XMAS with lights blazing, and a dryer that is on about half the time.
    This post was edited by an admin on February 2, 2013 12:32 PM.
  • RCO RCO @ 4:29 PM
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    Appreciative

    Gordy ...Don't get me wrong.  I'm appreciative of all the feedback on help.  I'm just getting frustrated with the whole situation.  I've attached a copy of spreadsheet with the breakdown of billing since we've owned the place.  I've added the columns highlighted in yellow as to what our costs and savings on electric would be over the time frame if we were:  1)  Dual Fuel  2) Off-Peak (Actually we were off-peak the 1st winter there and no one realized it.  We didn't have heat from 7 am to 11 pm each and everyday...if you recall from early posts.)  I've also attached the day by day usage for the last billing period that was so high.  I've highlighted the days we were there.  We actually got there around 11:30 PM on 1/23.  You'll note that some days are skipped but it is dependent on the time the meter is read so it could run over to the next day.  We did run a 110 infrared heater during the time we were up there to help out.  I gets chilly in the evening when the temp was below zero.  We also used the fireplace in the evening when we were there during that time frame.
    We also turn the heat down when we aren't there, turn off the water heater, and water pump.  The only thing using electricity that I'm aware of is the refrigerator.  TV, DVD player, and stereo are plugged in but off.

    Thanks!
    Ray
    This post was edited by an admin on February 2, 2013 4:54 PM.
  • Eastman Eastman @ 4:55 PM
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    Don't see the attachments

    ?

    Got it.
    This post was edited by an admin on February 3, 2013 2:08 AM.
  • Gordy Gordy @ 9:32 PM
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    I see it

    Seems you really do not use much more in terms of kwh while there maybe 6k at t the highest. Otherwise consistent during unoccupied times.

    Just remember that you still want AC so that could be killer. Depending on how much occupied, and temps.

    I think I would be cautious of predicted savings from the electric utilities. They just want to get you on board.
    This post was edited by an admin on February 2, 2013 9:36 PM.
  • Eastman Eastman @ 2:39 AM
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    Wish more people did this...

    RCO, I'm reading through the thread.  I commend you for doing what 99.999% of others don't; compiling the information into a mathematically communicative format.
  • RCO RCO @ 6:19 PM
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    Thanks!

    I appreciate the remarks concerning the data I've gathered. 
    We won't know for sure until April as to what the new rates will be for electric.  The price on propane when I checked last week up there was $1.89.  From what I understand, the current dual fuel rate of $.0552 is equal to about $1.33 per gallon of propane.  I guess that is figured roughly at about 90% efficient for propane system used.  At the current price of propane, an approximate break even would be $.07 KWH.  I realize that propane is probably at a high right now or at that time due to the cold weather they are experiencing. 
    It may be worth waiting until spring to do further action because:  1)  I'm already setup for the dual fuel or off-peak system.  I've a separate service for the boiler system and wiring is out to meter post.  The only issue is that the electrician would need to do a temporary jumper wire to a 2nd meter until it could be buried under ground and up through conduit.  2)  Fuel tank/line would be temporary due to same issues.  Each would need to come back out to bury lines in spring. 
    Are there boilers that are small enough to add a 2nd within the uitilty closet that houses the electric boiler?  I guess I'd prefer going with a dual system rather than giving up the electric completely.  That way I could still qualify for dual rate, use gas when more/if advantageous, and allow for supplemental radiant at a later time frame. 
    As far as A/C, we had one weekend this past summer where we really needed it.  I've picked up one window unit and plan on another for room above our garage to use when needed.  I'm not going to worry about A/C until we are able to use this place more on a consistent basis.  The only reason A/C came up was during the exploration of the mini-split systems.  That would have been the bonus of those.  I still have a contractor who tells me that a mini-split system will definitely lower my electic bills and provide the heat I need. 
    At the point of time that we do retire and spend more time up there, we will then probably look at connecting the garage and cabin to allow for another bathroom, wash room, and utiltity area.  Then we may look at other heating cooling options at that time.  That is 10 years + in the future.  Hopefully, we still have the place but only time will tell.
    Thanks again for the feedback guys!
  • SWEI SWEI @ 12:59 AM
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    arbitrage

    If this were by my place, I'd really want to know why it required so much energy for me not to be there.  The answer might well cause me to rethink ownership.

    If I could get a 50+% reduction per kWH via some token LPG implementation I would probably take advantage of it.  But not before understanding that first question.
  • RCO RCO @ 10:00 AM
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    Thermostat

    Hello.  Just got to thinking about the thermostat.  I had installed a new Honeywell digital thermostat back in late November of 2011 to replace the mechanical unit pictured within this thread.  It has seemed to do a better job of holding temp accurately.  It is a Honeywell RTH221B Basic programmable thermostat that I purchased at their local Wal-mart.  I've attached details per PDF. 
    Would it be possible that I could've hooked this unit up incorrectly or set it up wrong in which it would keep the boiler running all the time?  Just trying to think outside the box here!  It seemed pretty basic and I don't recall the details when installing.  Just want to rule that out as a possible issue.
    Thanks!
    Ray
  • cattledog cattledog @ 3:20 PM
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    high electricity use when not at cabin

    Hi Ray--

    It's possible that you are incorrectly using the temporary override instead of the hold when you reset to a lower temperature for unoccupied periods.

    https://customer.honeywell.com/resources/techlit/TechLitDocuments/69-0000s/69-2062EFS.pdf

    If there is nothing simple like "operator error" then you may want to have your neighbor go in when you are away, and verify that the place is a cool as you want it to be.

    If the neighbor is not available, then you might want to use Mr Google to find a low cost digital temperature data logger. You could also log boiler on/off time as well, but I can't remember if it is modulating or not and that could be a complexity.

    What is the payback time for the dual use rate to pay for the direct vent propane unit? What is the risk that the dual fuel rate schedule will be discontinued?

    Another thing to think about is if the power company actually uses its dual fuel rights and cuts you off, or limits your power where will you be with a small wall unit? Can you determine the past actions of the power company to see if dual fuel program power cuts are rare or frequent.

    Regards
  • Eastman Eastman @ 3:29 PM
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    If it's holding tempreture more acurately,

    Then I would think the unit is installed correctly.  Cattledog's suggestion seams more likely.  I take it you do not have internet access at the cabin?  There's quite an assortment of thermostats now that would allow you to check on the system and turn the temps up remotely before your arrival.

    Question:  What are the delta Ts across the three system loops?  Someone asked that along time ago and I think it got lost in the dialog.
  • Gordy Gordy @ 10:02 PM
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    DT's

    I asked it in the hopes of trouble shooting. But at this point with the sporadic short term use it may be difficult to get a steady state sample.

    This was initially to see if loops were all getting decent delta t's. in loops, and main supply/return.

    We know the boiler has a max temp of 135*

    The slab I believe is not insulated.

    Slightly under radiated for the heat loss. No heat in loft area.
    Can't remember what the actual energy audit said.

    We know from the kwh per day (11 avg unoccupied) that there is about 37500 btu's being used per 24 hour period. That's between the boiler, water heater, and any other residual power for fridge etc.

    So that is about 1500 btus per hour average.....rough estimate with out knowing other power draws.

    Don't know the set back being used.

    Looking back at the 2011 bill your not to far off from before you really started to,do something about setting back.......I think.

    458 watts an hour.

    Does not sound like a lot if you break it down that way.

    I know it sounds odd, but I just don't think an electric boiler puts out like a gas boiler if its anything like an electric water heater verses a gas one. But then we are talking recovery rates also in that aspect.
    This post was edited by an admin on February 4, 2013 10:17 PM.
  • SWEI SWEI @ 11:52 PM
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    slab not insulated

    in northern Minnesota?  When _was_ this thing built?
  • Gordy Gordy @ 6:19 AM
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    SWEI

    Oops it's insulated, under-slab, and perimeter, but it was never said how much. That was many, many posts ago.
  • Eastman Eastman @ 3:20 PM
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    Gordy

    I'm not getting the same result.

    I calculated just over 12,000 btus/hour for the 27 days the place was unoccupied in the last billing period.  That's about 3.5 kilowatts.
  • Gordy Gordy @ 8:25 PM
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    Watts the btus

    He's averaging 110000 watts a day that's 11 kw

    1kw= 3412 btus

    11x3412=37532
    37532/24=1563.83 btus per hour


    The 458 must have come out of my arse sorry about that one.
    I did not average the whole billing cycle. The11kw looked pretty much unoccupied avg. that's what concerns me is the unoccupied periods.


    Like I said rough average we do bot know temps outside or indoor setpoint in unoccupied periods.
    This post was edited by an admin on February 5, 2013 8:33 PM.
  • Eastman Eastman @ 8:41 PM
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    factor of ten

    110,000 is 110 kilowatts
  • Gordy Gordy @ 11:46 PM
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    Your right

    I was looking at the demand column on RCO spread sheet thinking that the 11 was kwh. Now I looked at the billing. Sorry
  • Eastman Eastman @ 12:02 AM
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    Doesn't that seem high?

    For being unoccupied?
  • RCO RCO @ 8:10 PM
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    Patient Group

    I appreciate all of the feedback.  This thread has gone on for a long time and has become quite confusing.
    I'll try to recap briefly, if I can, as to what has been done since the start:
    We took ownership in 12/2010.  Immediately noticed the drop in temp at night of 7 - 8 degrees no matter what the outside temp.  Realtor had contractor check system in January 2011.  Deemed boiler working as it should.  Unhooked outdoor sensor because it was buried in snow and set boiler temp at 130, I believe.  Opinion was that system was not adequate to keep up to temp in place.  Recommendation propane wall unit.  Realized not much space for such.  Then recommended slab thermostat.  Interesting.....is that if we were being controlled during the daytime, I wonder how he operated the boiler??
    We insulated the loft area in the knee walls extremely well as 3 beds are built into the walls.  Didn't do anymore to troubleshoot for the remainder of the winter.  In August, we had a heating tech recommended by boiler wholesaler to inspect system - Thermolec 34,000 BTU boiler with 3 loop system in 720 square foot slab.  Deemed it was working correctly and also hooked up outdoor sensor again.  The contractor recommended electric cove heat or baseboard panels in loft area.  Again system not adequate.  Heating tech noticed control box on outside of house.  Upon further investigation with the electric company, we found that we were being controlled on off-peak service.  No meter so company wasn't aware of it.  But radio controlled controller was shutting our heat down from 7 AM to 11 PM each day.  They removed control box to have service to heat at all times. 
    Heating season of 2011, we noticed that the electric usage was still quite high for the time spent there.  However, the temp was more consistent without dropping as before.  I replaced the mechanical thermostat with a digital unit the end of November of 2011.  Temps seemed to hold steady at set point....couple of degrees higher during the day.  Winter of 2011/2012 was quite mild in comparison to typical winters but still high usage. 
    Acquaintance from that area recommended mini-split system to help lower costs.  He was very pleased with his system.  Contacted 3 contractors for bids.  One contractor is still convinced that I will see a reduction in electric costs and they will help heat the place.  We added cellular shades to all of the 11 windows in the main area. 
    This heating season has been quite high as is shown on the attachment posted a few days ago.  We have been exploring options of supplemental heating for a dual fuel rate.  I tried leaving the temp set higher for the month of October but I believe the usage was higher yet. (Suggestions that it may be better to not set it so far back when we were gone.)  It was S65 higher than last year for that time frame with same rates. 
    We thought seriously about a vent-free system just to enable us to get the dual fuel rate and have for times when we would be controlled.  However, we have had many, many comments that this is not the thing to do because of moisture and potential health hazards.  Also felt we would have difficulty finding someone to install and service.  We have since been exploring the option of a direct vent unit.  Would like to get one that is around 82% efficient....highest that I've seen in researching...to supplement.  Also, this type has a minimal hole size cut through wall incase it is not the answer or need to change system down the road.  We still face the complex issue of somewhere to install such a unit except for the stairway landing which is shown in one of the pictures in this thread.   We do have 2 - 52" ceiling fans which we've not been running on a consistent basis in the winter.  Still trying to figure out how to reverse them for winter use.  They have remotes and no sign of switches on units.  May have figured it out with some help from the company but will check next time up.
    I do know that rates are going to be raised this April but don't know those figures as of yet.  Currently, we are at:  $.0943/KWH for general service.  Dual rate is $.0552 and off-peak is $.0425.  Dual fuel allows company to control you up to a 6 hour time frame generally later afternoon into the evening.  No more than 400 hours during a heating season.  Typically has been about 4 hours at a time this season.  Of course, off-peak is off from 7 AM to 11 PM.
    We only have the word of the GC to go off of when researching construction.  It has R19 in the 6" walls and R38 in the vaulted ceiling.  I know that it should have spray foam insulation in the ceiling but that would be cost prohibitive to do at this point in the game.  The GC also indicated that he was there when concrete was poured and the tubing was insulated underneath and around the perimeter.  To what extent of insulation used, I can't say for sure.  We also know that in speaking briefly to the electrician, he thought the initial idea was to put the loops in a sandbed under the concrete for a heat storage unit.  Therefore, the hookup of control box for off-peak service.  Somewhere along the line there evidently was some mis-communication! 
    As far as measuring temps on the floor in different areas and temps on lines, I've not done any of that to this point.  We are there on such a limited basis.  I did have some concerns about the new thermostat because I don't recall the programming to "hold" status rather than using the factory settings??  Also, I do recall that I needed to select a cycle time frame.  So possibly, I didn't set right??  As I indicated, it has been pretty much spot on accept for this last trip when it was below zero on each evening, it may have varied a couple of degrees.  We were also burning our fireplace which could've been causing more heat loss than any good. 
    We did have the electric company do a heat loss calculation based off the dimensions and info I gave them.  The heat loss is at around 32,800 I believe.  I'm attaching that as well.  Can't recall if I did that earlier or not.  But it seems that the existing boiler system is probably marginal in handling that loss.  Typically, we notice when temp is at 69 by thermostat, outside wall (north wall) where indoor/outdoor thermometer is located; the temp is 64 or 65 on that wall area.
    Anyway, we typically have the temp set at mid to upper 50's when not there.  Again, the only other appliance drawing electricity would be the fridge which is 4 years old so energy efficient.  We turn off water heater and water pump.  The summer usage for the past 2 summers we've owned it has been very consistent at an average of 190 KWH per month over that period.  So it gives us a pretty good idea as to what we're using for heat. 
    As mentioned many times throughout this thread, the objective is to lower our heating costs.  We just received a $5200 bid for installation of an 80,000 BTU propane boiler from the contractor that was out 2 weeks ago while we were there.  I understand that a bigger system.....probably not quite this big...would generate more heat.  But my thought is that unless we spend more money to add additional radiant options, we'll not get much more, if any, heat out of our floor to heat the place any better.  It's really an unknown how long we would see a payback in this expense as well as possible remodel plans down the road. 

    Thanks again for all the feedback.
  • Gordy Gordy @ 8:37 PM
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    Slab insulation RCO

    Is there snow melt around the perimeter of the foundation?

    A SLIGHTLY bigger boiler will allow higher supply temps to the slab verse the 135 you are bound to now


    I know one thing it's a long scroll,to the bottom of this thread every time I open a PDF, or do a post.
    This post was edited by an admin on February 5, 2013 8:39 PM.
  • RCO RCO @ 10:34 PM
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    Snow Melt

    Gordy
    No, I don't notice snow melt as I particularly looked for that last time up.  Will check agaiin the next trip as they've received more snow.....about a foot.
    Thanks!
    Ray
  • RCO RCO @ 10:34 PM
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    Snow Melt

    Gordy
    No, I don't notice snow melt as I particularly looked for that last time up.  Will check agaiin the next trip as they've received more snow.....about a foot.
    Thanks!
    Ray
  • Zman Zman @ 12:47 AM
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    Blower door?

    ME mentioned a blower door test earlier in the thread. An IR camera would not be a bad idea either.
    It seems as though the system is working as designed. A typical radiant system like yours will emit somewhere around  30 btu/foot. Judging by your energy bills, it is doing exactly that. There seems to be a lot of talk about a bigger boiler. I think the one you have is oversized compared to the capacity of your slab to emit. You could put an amp meter on the boiler if you want to see what is really going on.
    You could certainly put in a propane boiler and reduce your energy bill 30% or so. www.eia.gov/neic/experts/heatcalc.xls . You would however have to add some radiation to get any more heat.

    The real Elephant in the room is, Where is all the heat going? The kind of heat loss you are seeing is unheard of. Has the meter been checked or replaced? You could throw an amp meter on the main an "clock" It. 

    I think the next steps should be to verify that the meter is correct. Then do a blower door and IR camera survey.

    Carl
  • RCO RCO @ 9:25 AM
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    More Info

    Just wanted to give you one more piece of information to help this thread keep going!!!  Just happen to have all of the usage by day from time we took ownership.  I've also highlighted the days we were there and set temps as best as I can recall. 
    If I understand correctly, I'm getting the consensus that we are using too much energy even while away to keep the place to temp.  So, if that is the case, my best bet is to have some testing done to see where the heat is going??  I'll need to do some checking to find out who can do this for me up there. 
    I did find out yesterday that the new rates are going to be as follows:  $.1053 / KWH - general service, $.0602 / KWH - Dual Fuel, and $.0445 / KWH - Off-Peak.  So we will be taking a $.011 increase per KWH from what we are currently paying. 
    I've been looking at the Rinnai energy efficient direct vent heater.  I've attached a couple of pics that show where we'd like to mount this if we decide to go this route.  I'd prefer the larger, 36,500 unit but the 20,700 unit (29.5" wide with 2" clearance on each side as space is 36" wide on landing between wall and stair) would fit better in this space.  The 1st picture is of the bottom landing of the staircase and would blow heat towards the main living area....sectional, fireplace, and the dining area off to the right of the heater.  Again, this would be done after making sure we have the other issue covered in checking out the 1st issue.  The 2nd picture shows the utility closet that is directly behind the wall on the landing.  I believe the Rinnai has an extension kit that would allow for venting from the unit back to the outside wall (which would be along the right side of the picture). The vent in the picture was just installed in November of 2012 as we thought we might as well release some of the warm air that was trapped in the closet area. The Rinnai units appear to be the most energy efficient units @ 84% according to their brochure.
    Thoughts??
  • Zman Zman @ 10:21 AM
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    Red flag

    I think your energy usage is a major red flag.A heat loss over 25 btu/foot on the coldest day is cause for concern. 25,000 btu/hour / 3415 = 7.32 KW/hour or 175 kw in 24 hrs. That would be with the home at 70 degrees on the coldest design day. The days you are not there with the temps turned down should be a fraction of that. Those are the numbers that are most alarming.
    I would have a blower door and IR survey done.

    Carl
  • RCO RCO @ 10:49 AM
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    Thermostat

    I found an issue with the t-stat. First the Honeywell model is a111 not a 221. It is a basic non-programing for time of day settings. The only settings to program are Fahrenheit and Celsius and cycling frequency. That last item had me thinking about the stat since our last trip up. I checked it when we arrived this weekend and sure enough I had it set incorrectly. The instructions are basic and brief but somehow I had set the stat at number 5 which is for a gas or oil furnace @ every 12 minutes! I think it should be set at 1 which is for gravity / steam setting for 60 minutes.

    Th instructions don't go into detail on cycling control but I would assume this would have some impact on operation?? Possibly the boiler running to short a period more frequently??

    Thanks!
  • Gordy Gordy @ 7:18 PM
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    Setting

    Basically that setting is what takes the place of the anticipater on the old mercury t stats. This controls how much variation from setpoint is allowed. It does not mean your heat source will run every 12 or 60 min. It still needs a call for heat. It just decides how much below setpoint before it calls, and how close to setpoint before it shuts down. I do not think this would effect energy use to much at least to the extent your seeing.

    I should note I have a LUX t stat with the same feature. Why they call it cycles per hour I don't know. And my description of its function may be a little off.
  • cattledog cattledog @ 7:22 PM
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    electric boiler cph

    Ray-

    With an electric boiler, you are always nominally 100% efficient. I can't really think of a situation where overall system efficiency would be significantly decreased by shorter cycle times. Keeping the slab stable and not having large swings around set point is good.

    If you are only setting back to 55 unoccupied, you can go lower if you can arrange for turn up before arriving. I would also try and get the heating degree day data to go with your unoccupied and occupied usage to try and understand better if you really have high usage unoccupied, or are just paying the price for a cold Minnesota winter.
  • SWEI SWEI @ 1:52 AM
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    thermostat should

    really be a high limit controller if the ODR is setup properly.  It should turn off the boiler when your fireplace or woodstove elevated the space temp a few degrees above the indoor setpoint.
  • Gordy Gordy @ 7:50 AM
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    HDD

    Ray,

    What is your location in northern Minn.?

    Like to put some HDD to the usage to clarify things. If you don't mind.

    You have provided a lot of usage information but no real temps for the days. This can tell a lot about the structure your heating.
    This post was edited by an admin on February 19, 2013 7:51 AM.
  • RCO RCO @ 11:19 PM
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    Location

    Gordy - We are near Park Rapids, MN   56470.  My wife had the local gas company that sells/installs Rinnai heaters bring out a unit to see how it fit on our bottom landing to the stairway.  I've attached some pictures of the unit as it will be sitting if we go this route.  It's only a 20,700 BTU unit but have heard good reviews on this brand.  It fits the space nicely and can be vented out approximately 10 foot to the right of heater.  It is situated in a fairly good area.  We would probably be controlled mostly for 4 hour periods during peak demand times.  The cost of this unit, vent kit, and installation will be around $2100 with gas line, tank, etc behind garage.  Will cost $200 - $300 for wiring 2nd meter.  Shouldn't take long for payback on the savings for dual fuel rate.  I really can't think of a better option with quicker payback at this point.  Just concerned that this size heater will do the job.  I can't imagine the slab losing too much heat in the 4 hour span. 
    Thanks!
    Ray
  • nicholas bonham-carter nicholas bonham-carter @ 11:26 AM
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    Extra source of heat

    No one has mentioned an additional heat source--get more dogs!!--NBC
  • Gordy Gordy @ 8:56 AM
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    Different perspective

    Ray,

    Lets look at the boiler. It's 34,120 btu. So that is 10 kw consumption while on.

    If the boiler ran 6 hours a day. That would be 60 kw used in 24 hours. 6.60 a day at .11 cents a kw.

    That would be 198.00 a month. So you could do some deductions to,figure how much your boiler actually is on. I like my lux thermostat it tells how many hours in a 24 hour period there is a heat call which you can only go back to the day before, but it has a total also from the point of time its reset. You can figure out from there how much the boiler is actually on.


    From that info you could calculate degree days per sf. Knowing how much electricity is actually being used by the boiler to heat the space. If your in the 5 btu per degree day range the dwelling is not to bad for insulation. But you would need to do,those calculations at set point while occupied. To get a real good number.
  • RobG RobG @ 11:52 AM
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    Clearances For Stairways

    Before jumping the gun, I would contact the local building inspector to find out if the Rinnai unit will work in that location regarding clearances. (I doubt that it will).
    If it were my house, I would put in a Mini-Split. The unit(s) could be left at 50 degrees while unoccupied and turned up prior to occupancy. Then use the electric boiler as a back up. A heat pump is ALLOT cheaper to operate than an electric boiler, and you would have A/C. When funds permit, you could change out the electric boiler for a propane boiler to get the dual fuel rate. Until then, a heat pump would save  you allot of money on electricity.
    Rob
  • Gordy Gordy @ 1:37 PM
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    Heat pump

    It was -14 there this morning how do you suppose a mini split would fare with those temps Rob. Not questioning just asking.
  • RCO RCO @ 7:24 PM
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    Options

    I appreciate the feedback.  I'm growing weary of all of my research and analyzing this current system and structure.  I've not been able to find anyone local to really give me much help in a solution that will ultimately save $$ in operating costs in a reasonable amount of time frame. 
    I had a contractor I'd been in touch with who was kind enough to stop by on Saturday AM up there.  He builds energy efficient homes and has them tested  quite frequently for efficiency.  Obviously, I can't go back and redo insulation to make it more air-tight as it would be cost-prohibitive.  I had mentioned my thermostat finding and his suggestion was to install a simple slab stat to control the boiler system.  Then no matter what other type of heating supplement I was using, it would always maintain the slab setting to how the thermostat was set in conjunction with the outdoor sensor.  He thought the gas supplement wasn't a bad idea.  He didn't mention any huge, noticable areas of loss.  There is no sign of ice forming on the roof....snow is intact all over roof line with no signs of melting so I'm guessing we're not losing much heat that way.  I'm not saying it's completely air-tight as I know there are areas that could use more insulation.  Also the foundation area does not show any signs of melting so slab must be insulated in that area as we're told. 
    I'm thinking that my best option at this point is to go the supplemental gas heater route.  First of all, we don't spend a lot of time up there see how the system works for long periods of time at the higher, steady set point.  Secondly, we don't want to spend a fortune to possibly get a cheaper cost in a gas boiler setup.  Lastly, I would prefer to see savings right away which we would do so in cutting our electric rate between 40 - 45% on our heat. 
    I'm not sure on codes but the Rinnai unit needs to have 2" clearance on each side from any combustibles....no problem.  10" above the unit....no problem.  And 40" in front of the unit...again, not an issue.  It takes up approximately 10" of space on the landing and still leaves sufficient room to go around it up the stairs. 
    Thanks!
    Ray
  • Gordy Gordy @ 8:48 PM
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    Stairway access

    Would be an issue if its a 36" stairway you would lose 10 " of that unless you mount it 7' off the floor, or more.
  • Radiant Heat Issues

    If your cabin seems to have no problem heating up during the day, could solar gain be shutting down the radiant system, in the afternoon, and it has a hard time catching up because of the high mass slab? Have you checked for melting snow around the foundation? That could be the cause of the high heating bills, if the slab or perimeter insulation wasn't installed correctly. Thats my guess.

    Thanks, Bob Gagnon
  • Ericjeeper Ericjeeper @ 11:29 PM
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    Looking for a cheaper way to heat the outdoors.

    I have read through most of these post, You are simply loosing all of your heat out through those windows. granted they are pretty. But I would opt for some better glass. look for a triple pane, non conductive spacer system with Krypton gas.
      On a sunny day those windows are working in your favor but once a cloud or night fall rolls in. Your system falls back into catch up mode.
  • Eastman Eastman @ 8:55 PM
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    RCO...

    Love to dig this thread up and keep it going....
    First off, I can't remember everything anymore that has been discussed/not discussed  --I hope you don't loose your cool if it sounds like I'm rehashing issues you're already aware of.  I just don't want to leave something out that you might find important.

    Subject:  Are the fuel costs listed on your heat loss correct?

    I looked at your heat-loss-analysis.pdf.  Are the energy costs listed there correct?  Your freedom heating amount was $0.065 per kwh.  LP was listed at $2.05 per gallon.  Which is equivalent to about $0.075 per kwh.  (1 gallon of LP utilized at 100% efficiency has energy content of about 27kilowatt hours which, when you do the math that equates to $0.075 per kwh.

    So, just from an energy cost perspective you are getting a better deal with the electricity.  Installing the Rinnai unit and *not* using it is the best way to go here.  Then you can get the duel fuel rate which pushes the electricity price even farther down to $0.055 per kwh.  Now, If I remember correctly, it sounds like the utility shuts off the electric heat for a few hours in the late morning?  That is typically when a slab system is in the process of overshooting the desired temperature.  (Just like the undershoot in the evenings; slab and environment are out of sync)  So that is really a perfect scenario for making the most of a duel fuel system.

    Are you still experiencing a lack of heat in the evening?  If it were my place, I would install the LP unit merely to get the better rate, and use the fireplace or some other type of electric resistance heater for the evening auxiliary requirement.  Once again, purely from a cost perspective based on the rates provided by the utility, it's clearly better to use an electric resistance heater rather than LP.  However, personally, I would much rather upgrade the fireplace to a level suitable for daily practical use.  Your fireplace is really right where the heater wants to be, and given the way you use this place as a north woods retreat of sorts, it seems only natural.  Of course you would for sure want something that gets its combustion air from the outside and is reasonably efficient.  A third option, would be a cheaper gas wall furnace that is capable of running with or without the fan in case of a power outage.  Not as efficient as the Rinnai but it would give you peace of mind in case there's an extended power outage.  They're tall and skinny; consider putting one in the corner behind you're dinning table.

    New topic:  Here's my thoughts on where the heat is going. 

    #1.  Smaller homes require more btu's *per* square foot to heat.  Not total but more per square foot.

    #2a.  I really don't think you are reducing the heat far enough to get any significant saving while you are gone.  The house is in a really cold winter environment.  It's architecture and solar orientation are not helping.  When its -14 degrees outside, a setback from say 70 to 55 doesn't help that much.  I checked your billing information over one of the colder months and compared it to the heat loss information using a correction factor based on the average temperature at a nearby town during that time period.  *I got a decent match.*  Heat loss is proportional to the delta T between the indoor and outdoor temps.  The colder the environment is, the larger the setback required to achieve a noticeable percentage of savings on one's bill.  On the other hand, the good news is it wouldn't cost much more to actually live there. 

    #2b.  You're setting the thermostat back while you're gone but not the system supply water temperature.  Higher water temperatures imply higher thermal losses into the ground.

    #3.  Too much inherent system lag due to thermal inertia:  A small home needs a responsive heating system, particularly ones with extra windows and cathedral ceilings. Changes in outdoor temp or solar gain quickly translate into significant heating or cooling demand changes.  If the system can't modify it's output quickly enough it falls behind or overshoots.  Typically the occupant is forced to increase the thermostat setting and water supply temperature all day to maintain a minimum comfort level.  This in turn increases thermal losses through the slab and rest of the building envelope.  --Ultimately increasing your power bill.  Have you considered getting an internet connection?  There's a lot of thermostats on the market that can be controlled remotely, but more importantly, I believe there are units that are capable of receiving weather forecast data from the National Weather Service.  With this information, a slab system would be able to predict future demand changes instead of responding to them after the fact.  That would be a major improvement for you.  At a minimum though, I suggest adding an auxiliary heat source that can react quickly, with the floor temperature maintained for even base load.  That would give comfortable even floor heating with a faster response to occupant demands and changing weather.  With such a configuration you should be able to reduce your supply water temperatures and prevent some heat loss into the ground.

    #4.  Possible unresolved system issue, control issue, or lack of insulation.  Can you check the flow rates through the pex loops next time you're there?  Low flow may indirectly result in additional heat loss into the ground.




     
    This post was edited by an admin on April 2, 2013 9:05 PM.
  • RobG RobG @ 12:33 PM
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    Another Idea

    How about using a glycol solution for the radiant, install a tankless gas water heater (you will now get the dual fuel rate). A tankless water heater can be drained down in under a minute. Get a good plumber over to show you how to drain down and winterize the rest of the plumbing system. In a small place like that, draining the system should take no more than 15 minutes. Then you can just kill power to the home while it is unoccupied. USING NO FUEL!.
    Just Another idea.
    Rob 
  • Eastman Eastman @ 8:49 PM
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    Have you ever

    used any kind of system that can receive weather prediction data over the net?  I see Mr Pex is advertising a new system that "recieves a constant stream of weather forecast information from the National Weather Service."  I assume it uses an internet connection for this.  That seems like the best way to run a slab system.
  • RCO RCO @ 2:01 PM
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    Thanks for Continued Suggestions!

    I appreciate the continued support with suggestions and opinions.  I can update you to the fact that I have had the Rinnai heater installed a few weeks back in the location show in the previously attached photos.  I'm pleased with the quiet operation of this unit.  Although we don't use it much.  I'm waiting for the snow to leave and ground to thaw so I can get an electrician in to hook up the radiant system to the 2nd meter for the dual fuel rate.  As close as it was to spring and that fact that the electrician would need to make 2 trips ( 1 to do a temporary connection at the meter post and then come back to dig the line in from the 1st meter to the 2nd), I decided to wait to save on labor and 2nd trip charge. 
    So starting next fall when heating is needed, I will be on a dual fuel rate.  I'm anxious to see how this works for us. 
    I've read the comments concerning the windows and loss of heat.  We know that we have to deal with this issue.  Actually we are not getting much heat gain when we are not up there as we have the cellular shades down and curtains drawn shut. I actually work for a storm door and window company.  I've had thoughts of installing storm windows on the Andersen units to help.  We now offer Low-E storm windows.  At my cost, I could purchase 13 windows for roughly just under $1000.  I guess I'm not sure how long the payback would be on those??  Our information tells us that we can increase insulation over plain glass by up to 69% with the addition of a storm window with Low-E glass.  As we currently have thermal pane Andersen units, we of course do not have storm windows on them as the unit comes with a full screen that snaps into the frame on the outside of the window.  The storm window I'm looking at is our top of the line unit as we have Low-E availablity in the 3 series of our storm windows.  However, the best series is the only one that offers a color that would most closely match the exterior of the place.
    So, that is where things stand right now.  I'll report back next heating season as to how things are going.
    Thanks!
    Ray
  • Eastman Eastman @ 5:19 PM
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    What about the flow rates?!

    Can you check the flow rates?  You shouldn't have to wait more than a few seconds for the manifold readings to stabilize.

    And while I have your attention, seems like there has been several suggestions for internet controllable thermostats.  Is there some reason you are not considering this?  How much is a cheap dial-up connection in that neck of the woods?
  • RCO RCO @ 2:20 PM
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    Update on Heating System

    Just an update on my heating situation.  I now have my electric boiler connected to a 2nd meter for dual fuel rate @ $.0602 per KWH compared to the general which is at $.1053 per KWH.  I've not been up yet to use or has there been weather at this point to need the heat.  The electrician set the thermostat for the boiler at 50 for now and the Rinnai heater at 45, I believe.  Plan on heading up there this next weekend.
    I have been investigating thermostats that I can remotely control.  However, it appears that most all require an internet connection.  As we don't have a phone nor satellite there, it would definitely be an added expense per month...probably in the $50 range.  Which wouldn't make sense at this point.  I've started looking into it because my dependable neighbor is going to be moving to town next spring....bummer!  This will make everyone on our road seasonal. 
    I've done some reading on the Nest thermostat.  Although it also requires Wi-Fi connection to use remotely.  However, it does indicate that it works well with radiant heat.  I guess worse case scenario is that we can leave at 58 and use the gas heater and infrared to heat place up quickly when we arrive in  the winter. 
    I'll keep you posted as to how the new system works and costs for this heating system.  Hopefully, we'll realize some significant savings in our electricty bill.
    Thanks!
  • NYplumber NYplumber @ 10:22 PM
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    wood stove

    I recently spoke to a customer of mine with a small cottage in a very cold climate. He has electric baseboard as the built in heat source. He says his wood stove is the key to bringing the place up to temperature
    :NYplumber:
  • Eastman Eastman @ 7:46 PM
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    Post #159

    The detailed energy usage history available with nest along with it's integrated occupancy senor are excellent features.  However, I believe the usage history requires the device to be in communication with a nest account at nest corporate.  In other words, that feature probably requires an internet connection to really make use of.  I don't think it is directly accessible from the device.  (Somebody step in and correct me if I'm wrong.)

    Regarding the "True Radiant" feature.  I can't see how the device could have a chance of accurately predicting the response time of your slab unless an ODR is installed on the heating system.  It could certainly learn what is required if the weather remains steady, but that doesn't seem like a realistic expectation.  Does the nest monitor the outdoor temperature?  Likewise, your infrequent cottage usage pattern would probably exacerbate such algorithmic learning problems.
  • nicholas bonham-carter nicholas bonham-carter @ 11:28 AM
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    Internet thermostat

    Maybe you and your neighbors could share an internet connection for the remote monitoring.--NBC
  • nicholas bonham-carter nicholas bonham-carter @ 12:19 PM
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    Cogeneration?

    Would this be a place for cogeneration, with the waste heat used for the house?--NBC
  • RCO RCO @ 7:52 PM
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    Update Thus Winter

    Just wanted to post an update on electric usage/cost from December and January this season.  Based on the regular rate of $.1053 per KWH and the dual fuel rate of $.0602 per KWH, we've save approximately $250 over the past 2 months.  We have not used much propane with the Rinnai heater.....but also have had issues with it.  The gas company/installer has not been able to trouble shoot at this point.  We continue to have issues with the exhaust vent icing up which shuts down the system.  The installer was back out earlier this month to adjust the venting as we have an extended vent/intake of about 60 - 70".  He gave the venting more slope to the outside but found it was still icing up this past week.
    We've used more KWH this winter because of the extreme cold.  However, I'm pleased with the savings thus far.  So far this winter, we've been leaving the system at 59 - 60 degrees when we are gone and the heater at around 54 - 55 degrees.  I'm not sure if we'll save by turning the radiant back to 55 and the heater to 50??
    I an considering a couple of things.  One is to install a slab thermostat...possibly a Tekmar 518??  As I've indicated in the past, the temp at the outside wall has been 5 - 6 degrees less than the thermostat temp reads via air sensing. 
    I'm also looking into replacing the existing the existing fireplace doors with a more air tight system with a blower.  I'm not sure if there are some economical ones out there but just want to be able to get more efficiency while burning wood.  Something to keep more of the warm air from inside going out the chimney and a fan to get the warm air out into the living area.  The current fireplace does have an outdoor air intake.  But doors are rather leaky and no blower.
    I've appreciated all the feedback!
    Thank you!
  • Gordy Gordy @ 8:17 PM
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    Fireplace

    As far as the fireplace goes other than an airtight high efficiency insert not much you can do with it. You have an outside air intake which helps. You won't really find "air tight" doors which may create problems if you could find them. Outside air intakes are not meant to sustain combustion alone, but are meant to reduce air taken away from the interior of the house, and in some cases if wind direction is right can actually suck air out of the fire box.
  • Eastman Eastman @ 2:53 PM
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    setback

    If I remember correctly, you are hardly at this location, correct? I would lower the temperature to around 50 for the electric, 45 for the space heater. 10 degrees is not a significant setback in that climate. You would save roughly twice as much.

    Ideally the system supply temperature should also be adjusted lower while you are gone.

    Yes on the slab sensor, but you might want to consider a two stage tekmar thermostat. If you are still having temperature control issues, the second stage could kick on something else, perhaps the rinnai, but I kinda doubt that heater can interface with a conventional thermostat.

    Other things to consider: there are thermostats that are controllable by phone (without internet), and a basic landline is usually pretty cheap. They could also probably be configured to call you if the temperature drops to low.

    "As I've indicated in the past, the temp at the outside wall has been 5 - 6 degrees less than the thermostat temp reads via air sensing." -not sure I understand your concern. Are you worried about where to put the stat or are you hoping the slab sensor will eliminate the 5 degree difference?

    Regarding the fireplace: I have a similar setup with outside air. Check the interface between the masonry and metal trim of the doors. For me, that was the biggest spot for air leakage by far. I also have a device on top the chimney that closes the flue when not in use.
    Unfortunately the glass blocks the radiant energy and those blowers don't extract much heat from the fire.
    This post was edited by an admin on February 2, 2014 3:05 PM.
  • RCO RCO @ 6:37 PM
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    Setback

    Thanks for the advice the setback.  We've typically set the t-stat lower in past winters decided to try 59-60ish this winter.  Will definitely try that the next time up to see how that works for us.  Need to make sure our backup is functioning as it should be for times when electric is controlled. 
    My comment on slab thermostat was touching both of your points.  Mainly wondering if the slab stat would make the outside wall temp more consistent with the existing area where t-stat is located.  However, the current t-stat is located on wall of closet holding boiler so  not sure if that is the place in which you would want to place the probe?? 
    Are you referring to adjusting the water temp on the boiler while we are not there as well?? Also it sounds as though you can get a t-stat controllable by regular phone vs. internet?  We have neither there but lines are to the house for phone which would probably be cheaper than internet.
    Yes...not sure I want to spend a ton of money on fireplace insert.
    Thanks!
  • Eastman Eastman @ 7:41 PM
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    tstat

    The sensors for the stat should be measuring spots that are representative of the living areas you want to control. Tough call in your case, generally an outside wall is considered bad, but I don't think you have too many inside walls. Closet may not be the best location either, but I don't really know where that is in relation to the rest of your home.

    Even if you put the tstat at the outside wall, it will not correct the temperature difference, it would simply increase the temperature of the whole home. You really need to adjust the system's delta T if you wish to affect the floors distribution patterns. This would require a change in the flow rate.

    "Are you referring to adjusting the water temp on the boiler while we are not there as well??"
    Yes, you may gain additional savings by running at a lower temperature. This may reduce thermal losses into the ground and at the perimeter of the slab. However, I don't think there is a way to adjust that setting without taking the cover off the boiler and exposing you to potential electrical hazards.

    I can't recommend any particular phone controlled tstat, I just know they exist. A basic phone line is like 10 to 15 dollars. Call a day ahead and reset the temperature. Forgot to turn the temp down, call and reset it. I'd want one that could call me if the heat goes out.
  • SWEI SWEI @ 8:00 PM
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    A basic phone line is like 10 to 15 dollars

    in a few jurisdictions, yes.  But even there, the total monthly bill will probably be closer to $35.00
  • RCO RCO @ 2:03 PM
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    Phone Line Access

    Just checked with one of the phone companies up there.  A basic phone line is $14.50 per month......with taxes and federal excise fees it is roughly $20 - $25 per month. 
    I'm somewhat limited as to where I can access a space to insert probe for slab thermostat.  Maybe it would be worthwhile placing it towards the back side of the closet area closer to the outside wall??  The closet that houses the boiler system and exhaust/intake venting for the gas heater goes under the stairs leading to the loft.  I don't have very easy access to try to place the probe under the landing of the stairway outside the closet unless I would run the line behind baseboard to place probe in from front side (see pictures above of landing where Rinnai heater is sitting).  This would possibly give a more accurate reading than inside the closet??
    Thank you!
  • Eastman Eastman @ 1:15 PM
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    something else to look into

    check this out: http://allthingsd.com/20060125/connect-cellphone-home/

    Looks like there is a way to connect a cell into a regular residential phone system. I'm curious if you could get it to work with a phone thermostat. -can't see why not.

    Combine this adapter with a prepaid cell. You can get a pageplus 1 year contract for $80, and there's no taxes. Trackphone and others may have similar plans. This gives you 2000 minutes on verizon's older CDMA network which tends to be the best for rural areas from what I hear. Maybe track phone would be better in your specific area.
    This post was edited by an admin on February 5, 2014 1:17 PM.
  • RCO RCO @ 7:50 PM
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    Surprising Electric Bill

    OK. Our electric costs have been considerably lower this winter due to dual fuel service. Probably heating costs have been better due to the fact that we found out our radio control unit was/is not working properly to control our electric boiler when needed! We've contacted an electrician to check this out our next trip up.

    Anyway, our last month's billing from 1/28 - 2/25 was $175 which included 126 KWH - general electric & 2127 KWH - electric heat. We were there on 2/6 - 2/9 in which heat was turned up from 55 or 59 degrees to 70 and then back down to 59. It was also turned up on 2/14 to 70 and back down on 2/15 in the afternoon to 55 or 59. This was due to the unfortunate issue of quests using our cabin and arriving to find the water line frozen from well to cabin.

    So I was surprised to see this past billing, 2/25 - 3/25, to be $48! This included 102 KWH - general electric and 55 KHW - heat electric. This is the first time in which we have no been up there nor has temperature been changed during a billing cycle during the winter. Could this be possible?? Is the secret in leaving the temp at a constant?? I've attached copies of temperature averages for those 2 billing cycles. PS We are having someone check this weekend to make sure we have heat!!
  • Eastman Eastman @ 12:59 AM
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    not possible, floor is not working

    55 kilowatt hours for a month is roughly equivalent to the output of a 75 watt bulb.  At an average temperature of 11 degrees F, it's clear the floor is not working.  Did your guests turn up the thermostat for the rinnia?

    Do you have enough propane to run the system for over a month?

    What is the radio control unit that you spoke of?
    This post was edited by an admin on March 29, 2014 1:04 AM.
  • Gordy Gordy @ 9:26 AM
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    Propane usage

    Have you compared that with the low electric bill time frame?

    Agree with Eastman.
  • RCO RCO @ 11:22 AM
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    Thanks for Response

    No, I do not know the settings on the gas heater. I don't believe it was touched as the radiant heat would've been adequate upon arrival. But don't know any details. I will hopefully have someone check it out later today. I'm having this person check the boiler, breakers, heater setting, and propane usage.

    Thanks!
  • Mark Eatherton Mark Eatherton @ 11:37 AM
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    Get ready for pocket/wallet shock...

    The cost of LP where I am at exceeded the cost per therm for electricity. Polar vortex = demand outstripping LP supply and price went through the ceiling....

    Just warning...

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • RCO RCO @ 1:09 PM
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    Propane Costs

    Thanks Mark! Yes, I know the price has been crazy this winter. I've not added any to our tank since early fall fill up. The last time up in early February the gauge indicated between 60 - 70 so don't know where we are at this point. We had the heater set at about 54 so would kick on when electric boiler was controlled. However, we had received notification in February that for some reason the electric company didn't believe they had been controlling our heat during severe cold periods. They had a technician out to the place to check the wireless control unit and said it wasn't working. So, I'm assuming that situation helped us on propane! We notified our electrician who contacted the company. He said that was all that was needed to be done until we get up there and he would check the connection to control unit.

    I'm not sure of worst case, if we've had no heat?? Our water pump was shut off and lines drained before we left in early February. Our guests using it the next weekend found that we had no water as line between well and cabin was frozen (common problem up there this winter) as frost reports have been in the 10 - 12 foot depth in some areas. So we should have no water leakage issues.

    I've someone checking this afternoon so will know shortly what seems to be the issue.

    Thanks!
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