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    Radiant Heat not Heating (89 Posts)

  • smittyal06 smittyal06 @ 9:02 PM
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    Radiant Heat not Heating

    This past winter we were not able to keep your house warm with infloor radiant heat. This was our first year in the house as we bought it as a foreclosure.  I have had 3 heating companies over and I was given this site by the last for some additional assistance. None of them seem real up to radiant systems. The house is heated by an outdoor wood boiler which is an open system. It comes through a plate exchanger to a closed system. The basement (about 1000sq concrete) stayed plenty hot with the system. However, the main floor (1000sq.) and upstairs (800sq) only would make it to 60 degrees. This was with everything running 24/7. The infloor tubing is 3/4 inch and has one run between every joist. It has insulation under it. The water coming in was hot so you could not hold on to the tubes, and on the return it was still warm. However, it was not heating our house. I have included a picture of the current set up. I know this is very vague, but I am not sure exactly what other information you may need to know. If you have any suggestions as to how to make this work better so we can actually stay warm, I would greatly appreciate them. Thank you.
  • JStar JStar @ 9:06 PM
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    What model and size boiler? Any pictures from a view with the boiler as well?

    I see at least a handful of problems already.
    - Joe Starosielec

    Guaranteed performance. Guaranteed energy savings.

    Serving all of NJ, NYC, Southern NY State, and eastern PA.
    Consultation anywhere.
    (Formerly "ecuacool")
    This post was edited by an admin on August 12, 2013 9:07 PM.
  • smittyal06 smittyal06 @ 10:12 PM
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    We use an outdoor wood boiler. The brand is subzero. Not sure on model, but it is plenty large to heat the house.The electric boiler does not get used.
  • Zman Zman @ 11:39 PM
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    Without a drawing or a wider view it is hard to tell what is going on in your boiler room. I agree with J star that there are some things that look suspect.
    One 3/4" tube every 16 inch does not make for much of an emitter. Is it stapled or hanging? Does it have plates or fins on it? I would guess that a bare tube assembly like that would have trouble making more than 10 btu/ft. I imagine your house loses more than that.
    Have someone do a heat loss calculation and add the appropriate emitters. Panel radiators come to mind.
  • smittyal06 smittyal06 @ 11:21 AM
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    It is a staple up system. There are some generic fins on it. I don't think they radiate much heat away from the tube.
  • smittyal06 smittyal06 @ 12:15 PM
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    Heat Loss

    I used the Slant/Fin heat loss calculator app to calculate heat loss on the main and upper floor. I came up with a value of 37,000 BTU/Hr. Does that seam plausible? 
  • Gordy Gordy @ 7:39 PM
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    On the emitter side. You have insufficient tubing centers to heat the space. Plates, or no plates.

    Need data on floor detail.

    What are your floor coverings on main, and second floors. The higher the r value the worse it gets.

    Also what temps are being run through the loops? Flow rates?
  • Rich Rich @ 7:57 PM
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    Sounds like

    the Company with the Orange dominant logo has struck again . Have had homeowners ask me to install internet purchased systems before .  Not good .
    You didn't get what you didn't pay for and it will never be what you thought it would
  • Tom Tom @ 7:08 AM
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    The first thing I would check is the plate exchanger, I had this problem on a house in New Hampshire. His plate exchanger was so plugged it you couldn't blow through it. If its possible for you to remove it without a professionals help thats where I would start, if there are no valves then I would call someone to come do that. If it's plugged you can try cleaning but it may be beneficial to replace keep the old one toss it in a bucket of calcium eating fluid and in a few months you have a back up.
  • smittyal06 smittyal06 @ 11:10 AM
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    The exchanger was just put in last October. I wouldn't think it would be plugged? The lines were all run when the house was initially built, but the pix you see was all done last October when the outside wood boiler was connected. 
  • Zman Zman @ 9:23 AM
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    If the exchanger is bad, you would not be getting enough heat or flow. Since the slabs work fine and the staple up is too hot to touch., it seems unlikely. How hot is the return on the staple up?
  • smittyal06 smittyal06 @ 11:19 AM
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    The return is a little warm, but nothing like the supply. I wish I had thermostats on each end.
  • Zman Zman @ 6:24 PM
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    How about posting some pictures of the piping.
    It sounds like your delta t is high between supply and return.
    You may also have low flow. If the zone has a mixer, what model.What size circulator?
    This post was edited by an admin on August 16, 2013 6:40 PM.
  • smittyal06 smittyal06 @ 1:19 PM
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    Here are some additional pictures of the system.This first is the piping coming from the outdoor wood boiler to the plate exchanger. The second is the other side of the plate exchanger. The top is the incoming and the bottom is the return. It goes up then to the 3rd picture to the tank. From there it goes down to the 4th picture. It head to the right through the mixing valve to the circulation pumps and down to the basement loop which is working good or the return. The 5th picture is the 2 pumps. One controls the main floor and one controls the upstairs. The 6th picture is the return from both the main floor and upstairs. That heads up to the top of the 7th picture to the top right just below the mixing valve. That then goes down to the basement loop or return as in previous picture. The 8th picture is the tubing in the joist. There is a little over a 2" gap from the tubing to insulation, and then the ceiling boards. The tubing is hearing hardwood floors on the main floor and laminate on the upper level. Please let me know which additional pictures you need or information would be beneficial. I appreciate the input.
  • SWEI SWEI @ 1:36 PM
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    Pictures 1 and 2

    appear to show a heat exchanger which is bypassed on both sides.
  • smittyal06 smittyal06 @ 5:41 PM
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    Yes, that is true in the picture. Sorry for being misleading. When in work, the valve in pix 1 and in pix 2 are both closed. They are open b/c we used the electric heating unit at the end of the season to try to heat the house to see if it was a boiler issue. However, the electric boiler did not produce any better results.
  • SWEI SWEI @ 7:04 PM
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    Just checking

    having missed my share of (even more) obvious details.
  • smittyal06 smittyal06 @ 1:26 PM
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    Delta T

    I feel the Delta T is high. How do you lower this? Is it a matter of shorter loops?
  • Tom Tom @ 5:40 PM
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    In the New Hampshire job I couldn't touch the supply because it was so hot. It flowed just enough to get the supply screaming hot but not enough to flow to circulate through the system and get any return temps. Could be a system pump problem or piping or plate exchanger. I agree with Zman lets see some pics.
  • Chris Chris @ 10:16 AM
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    You Have Flow

    House wouldn't heat to 60 if you didn't.

    The first thing to do is to re engineer the radiant system. Have a radiant heat loss and design calculated using the existing loops lengths etc. How would you be able to determine the needed water temp without it? Room again, is heating to 60 so you are transferring btu/hr out of the radiant.

    Look for the 2" air gap between the tubing and insulation. No gap, no transfer of heat. Basically in the is application you are creating a convection oven in the bay. Need that gap.

    You can stare at the boiler room all that you want, means nothing without knowing the heat loss and water temp required.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • smittyal06 smittyal06 @ 1:09 PM
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    Air Gap

    There is a 2" air space between the insulation and tubing.
  • Zman Zman @ 1:01 PM
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    Where to start...

    I absolutely agree with Chris that the emitters are suspect. Some investigation and math should be done.
    Any time you have a supply temp that is too hot to touch (140+?) and a return temp that is slightly warm (90-?) , I am going to think you have a flow issue. The flow issue needs to be addressed either way , so why not start there. The delta T will only get worse as the emitters improve. I would expect a delta T in the single digits in the system he describes.
  • Chris Chris @ 5:47 PM
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    Chasing a Ghost

    Your chasing a ghost and putting the cart before the horse here. Take the time and have a radiant heat loss and design performed based on what's in the floor. You don't even know what water temp you need. As a matter of fact you don't even know if the existing system can even get you to where you want to go. Like any lost sole in a jungle, a map comes in real handy and that heat loss and design is your map..

    Willing to bet there isn't enough tubing in the floor. Heck, you don't even know if those pumps are sized right. How would you, you don't know the needed gpm and at what head loss you have to overcome..
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
    This post was edited by an admin on August 20, 2013 5:50 PM.
  • smittyal06 smittyal06 @ 12:34 PM
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    In reading the numbers on the tube, I could figure out that one run on the main level was 462ft. long. Which I know is too long. 
  • Zman Zman @ 6:10 PM
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    I am really not seeing the harm in spending some time seeing if there are issues in the mechanical room before deciding to tear into a full redesign. Right off the bat with very little effort it seams obvious that the delta t is too high, indicating low flow. It could be that the position of the valves on the heat exchanger bypass is the entire issue. Maybe it is something else that is real simple.
    It is kind of like tearing apart your motor looking for a problem only to find out the car is out of gas.
  • Gordy Gordy @ 7:54 PM
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    High delta t

    Could also mean that there is insufficient emitter, and the btus are getting pulled off the train before it reloads at the station. May be beginning of loop is in a high load area.

    Could also mean excessive loop lengths for the tubing size, and circulator.

    But then again these could all point to flow rates. Like Chris said your only guessing.

    If we are guessing though, and tube centers are 16". Supply is to hot to touch, and return is a lot cooler. Then it's a combination of not enough flow, emitter,possibly insulation detail is not correct.

    I'm only seeing 4 loops seems like not enough loops for three floors worth of radiant even at 16" on center. Long loops?

    To add those plates are not the best let alone the installation of them.
    This post was edited by an admin on August 20, 2013 7:55 PM.
  • Gordy Gordy @ 8:45 PM
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    To the OP

    The best thing you can do is invest in an IR temperature gun. Install thermometers on supply, and return of each loop, and calculate loop lengths.

    Along with the heat loss of your dwelling.

    Once you know the heat loss of each zone, or loop. We can then do the math to see if what you have can be enhanced to meet the loads required.

    This could mean larger circs, extra loops, higher average water temps, insulation detail etc.

    With out the load call we are stabbing at it.

    I think you are producing the btus needed, you just have to get them where they need to go.l
  • Chris Chris @ 9:17 PM
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    The OP says he can get the thermostat to read 60. He is moving btu/hr. In my opinion that large delta is being caused as to one of your points Gordy, being taken off the train. Another issue I see with those plates is that a portion of the tubing may be right up against the sub floor. Wood is an insulator and may be stripping out the btu/hr so Gordy's IR thoughts to shoot the floors would show high surface temps where tubing is.

    I saw the four loops as well and that tells me there is either no way enough tubing in the floor and/or loops lengths are awful long and pumps may not be sized correctly as well.

    All is mute without the heat loss and doing the math.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • Tom Tom @ 7:36 AM
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    All is "moot"

    Chris just a heads up its "moot" not mute

    If smitty is saying that with either system the house won't heat then a heat loss is a good starting point.

    Smitty, maybe we can see a couple pics of the whole system, like entire piping layout at least another shot under the original post pic. Your symptoms could be a lot of things so it would be good to start at the first step then proceed. The way I see the system from the pic is there is no system pump or anything pumping the main loop. What's pumping water through the heat exchanger?
    This post was edited by an admin on August 21, 2013 7:41 AM.
  • Rich Rich @ 7:42 AM
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    Whole system

    from a distance is a great idea as opposed to segmented views . 
    You didn't get what you didn't pay for and it will never be what you thought it would
  • smittyal06 smittyal06 @ 12:41 PM
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    Here is the entire system.
  • smittyal06 smittyal06 @ 12:05 PM
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    The pump on the outdoor wood boiler pumps the water through the heat exchanger for the incoming. 
  • Rich Rich @ 7:28 AM
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    Delta T

    seems to be the issue here .  Install the appropriate 00VDT from Taco , set the Delta for 10* Delta and call me when you are toasty .  I know it's not quite that simple but the Delta T 00's have made plenty of horribly designed / installed jobs where there were unknown factors a snap for me . Some used the 0013 , most we used the 008 , but in most instances they worked real good and made us look like geniuses . If more work is required after that step the pump stays and is a great feature on any install because you are controlling closely the Designed For Delta .   
     Quite possible the original installer did not account for the Cv through mixing valves and accumulated head losses through Hx , mixing , and long loops .  I do believe that 2 008's may very well solve the problem , like I said , it's a Good starting point . Start with the obvious . Anyone disagree ? 
    You didn't get what you didn't pay for and it will never be what you thought it would
    This post was edited by an admin on August 21, 2013 7:34 AM.
  • smittyal06 smittyal06 @ 12:13 PM
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    So replace the 2 current pumps with the Taco units and you think this may clear up the problem? I am getting the feeling from reading posts that there may not be enough pex running through the house to still supply enough heat? Could the pumps compensate for that if that is the issue?
  • Rich Rich @ 12:25 PM
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    the existing pumps with VDT's should solve the Delta T issue at which point you can determine if there are any other issues . It is a fine starting point and makes sense before undertaking a deep retrofit , which if that is necessary these pumps will make those fixes and the system proper as the system will have a very close to designed for Delta T at any condition .  Again , it just may solve the issue for small investment . Needless to say closer spacing and different install method could lower your temps among other things , the 16" spacing may work . Don't know how tight the building is . Personally I would not design for 16" ever .
    You didn't get what you didn't pay for and it will never be what you thought it would
  • Gordy Gordy @ 10:13 AM
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    Since the HX was bypassed using back up boiler with similar results we can conclude that the head loss from that component is not part of a flow issue. Cv from mixing valves etc yes.

    Couple the fact it's 3/4" pex. I'm inclined to believe if the installer used 3/4 pex, 16" spacing, they probably had no clue on sizing circs, or maintaining acceptable loop lengths let alone understand water temps and flow rates .

    Delta t pumps while a great tool when designed in to a system it troubles me when they are used as a bandaid for poor piping practices. Sometimes it's the most cost
    Effective approach for righting several wrongs
  • Rich Rich @ 12:07 PM
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    that these pumps are much better when designed into a system . They are able to correct a lot of sins and let's face it often the only economically feasible fix . I honestly have to say that no matter what type of system I am designing nowadays I use them , only variable is whether I can get the losses down low enough to use the Delta T ECM .  I also wish that all are aware of what we are but we both know this is not the case .  Would you agree that this is a good starting point ?
    You didn't get what you didn't pay for and it will never be what you thought it would
  • smittyal06 smittyal06 @ 12:20 PM
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    With winter approaching I am not sure the route to take. I have no issue with tearing out the basement ceiling and rerunning proper loops with proper spacing and proper insulation. However, if that is the issue that only helps the main level. In which case the main level and basement would be heated. I have to still worry about the upper level. If I am already tearing out the ceiling in the basement to rerun loops, would it be a better option to use forced air on the main level as it would rise to also heat the upper level? Or would using water baseboard heating be a better option as the convection would also rise to heat the upper level? 
  • Rich Rich @ 2:01 PM
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    approaching . I would say that there are some of the brightest minds in the industry right here .  I would be willing to look at the room by room and give calcs , possibly some others would do the same . You , my friend should take advantage of the assistance offered here . If you are willing to tear down and redo the information will be invaluable to you .  Some of the rooms that are done may not meet the criteria to be on the same zone ( btu sq ft req , use pattern , similar finish floor) that some of us know about . Be sure to include your design day criteria . Do the upstairs too and basement , there may be a solution to your problem . Type of windows and doors also .
    You didn't get what you didn't pay for and it will never be what you thought it would
  • Chris Chris @ 12:38 PM
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    HEAT LOSS!!!!!

    Last time I say it. This thread is 8 days old and still no heat loss.
    It's now time for you to take a few hours of your day, measure
    the house and do a room by room heat loss. I'll even do it for you.

    Coldest Day of the Year Temp. 0 Degrees?
    Room sizes
    Out side wall length
    Ceiling height
    Window sizes
    Wall Insulation
    Heat Above? If no, Ceil Insulation
    Heat Below? If no, Floor Insulation
    Finished floor surface in Room

    Provide above for each room in the house.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • smittyal06 smittyal06 @ 12:45 PM
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    Already posted

    I used the Slant/Fin heat loss calculator app to calculate heat loss on
    the main and upper floor. I came up with a value of 37,000 BTU/Hr. Does
    that seam plausible? Do you need it room by room or total like I have. I figured it out room by room and added them all together.
  • Gordy Gordy @ 1:28 PM
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    20.55 btus sf

    If your sure you used the right values then this is a starting point.

    A value for each zone is helpful. You need to figure out what rooms are covered by each loop.

    Next thing is types of floor treatments in each of those zones.

    You will be lucky to get 15 btus a sf with your emitter set up depending on the r values of the floor covering. You are at .75 already with 3/4. Plywood

    This is why you are only getting 60* room temp running 24-7

    You are producing enough btus just can't get them off the train not enough stations to get off if that makes sense.
    This post was edited by an admin on August 21, 2013 1:34 PM.
  • Chris Chris @ 2:21 PM
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    That Will Work For My Experiment

    In your original post you have the 1st floor as 1,000 sqft - I see 4 loops in total in the picture. Are there 2 loops for the 1st floor and 2 for the second? What was the heat loss for just the first floor and what are the finish floor surfaces? 3/4" Oak?
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • Tom Tom @ 1:35 PM
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    One more pic.


    I can't see the return pipe behind the black box
  • Chris Chris @ 2:32 PM
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    Smitty Experiment

    Ok. You said your 1st floor was 1,000 sqft and your total heat loss is 37,000 for the entire house. I used 16,000 btu/hr for a 1st floor loss and treated the entire 1,000 sqft as one open room. See attached! This is with 8" on center. Those flimsy plates might get you 10 degrees less water temp but I have double in the floor then what you have for tubing!!

    In the end you don't have enough train track on your rail.. See experiment 2. This is where you should be not where you are..
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
    This post was edited by an admin on August 21, 2013 2:48 PM.
  • Gordy Gordy @ 6:31 PM
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    What it's showing

    Is 5 loops of 3/4" for suspended tube, and 8 loops for 3/8" joist track plates.
    This is only for one floor. You have 4 loops for 3 floors.

    If you have no problem correcting the error, all is not a disaster on the main floor. Just add loops to get your 8" on center with plates the extruded omega type. You will lower your average water temp. Have more even heat across the floor.

    This involves some repiping in the mechanical room to allow for the extra loops.

    The basement is not a loss as you said that heated well.
    This post was edited by an admin on August 21, 2013 6:33 PM.
  • smittyal06 smittyal06 @ 3:36 AM
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    There is actually 2 loops per floor. 2 basement, 2 main, and 2 upper. It would be best to take out the 3/4" and run it all 3/8" correct? Is this also better then going 1/2"? What type of plates should I use? I still question this however. If I get the main floor run correctly and that is heating well, is this going to help at all with the upper level? That is why I posed the question of possible going forced air or radiant baseboards to help heat the upper floor from the main floor. I do not wish to rip out the ceiling on the main floor to fix the upper level if there is other options?
  • Gordy Gordy @ 5:16 AM
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    Okay so that means you have

    2-350' loops in the basement
    2-350' loops on main floor.
    2- 280' loops on second floor.

    Add leader lengths from manifold and back to those lengths.

    This is provided they used 16" spacing through out.

    You are only looking at a little over 4' of head in your loops at 1.5 gpm. If that's what the flow rate is. What size are the circs?
    This post was edited by an admin on August 22, 2013 5:29 AM.
  • Gordy Gordy @ 6:05 AM
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    I see

    One pair of loops that is reduced down to 1/2" supply. Your trying to feed two 3/4" loops with 1/2" pipe. 1/2" will carry 15000 btus.
  • smittyal06 smittyal06 @ 3:42 AM
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    Heat loss numbers per room

    Main floor heat loss: 23,801
    bathroom: 1915
    laundry: 1157
    bedroom: 2416
    kitchen: 3201
    dining: 5007
    living: 10103

    2nd floor: 14052
    bedroom: 5402
    loft: 3282
    office: 2334
    bath: 3044

    With adding loops to the main floor and it sounds like I should be creating different zones, is a zone just a loop? Also, the main floor has only 1 thermostat. Is that an issue with adding more loops or zones?
    The main floor kitchen, dining, and living are basically one large room. There are no walls between these areas. It is just one large open area with lots of windows.
    This post was edited by an admin on August 22, 2013 4:36 AM.
  • Gordy Gordy @ 5:27 AM
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    A zone can be what ever you want to make it.

    Each floor could be a zone, or certain rooms.

    In your case I would treat each floor as a zone.

    If you can add enough base board, or panel rads on the second floor so they can run on the same water temps as the radiant it's an option.

    Still need to know a few things Smitty
    Circ size

    Floor coverings

    Btu output of heat exchanger

    Back up boiler output.

    Water temps you were running.
    This post was edited by an admin on August 22, 2013 6:02 AM.
  • smittyal06 smittyal06 @ 6:13 AM
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    would I be able to run a baseboard on the second floor though  without having access to the piping?

    The main floor is mostly hardwood. The bathroom and laundry are tile.
    The second floor is mostly wood laminate. The bathroom is tile.
    The boiler water temp was 170 degrees.
    By circ size do you mean the pumps? They are Grundfos UPS15-58FC 1/25HP
  • Tom Tom @ 7:54 AM
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    Am I the only one here that thinks the header piping is extremely poor? I can't figure out why they piped it the way they did. I only see the zone pumps and nothing else pushing it through the plate exchanger (on the pressure side)and the electric heater. If that's the case the zone pump is pumping through long tube lengths and through the plate exchanger and because I can't see otherwise its also pumping through the electric boiler, seems like a serious lack of flow. Perhaps I'm not seeing it right or there a primary pump in the electric boiler.
  • Zman Zman @ 8:51 AM
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    You are correct.
    It is great that we now have a heat loss calc we can now verify that the emitters are too small.
    I am glad no one tripped over the 800 pound gorilla in the boiler room. It would be absolutely impossible for the system as piped to deliver the water correctly to the (theoretically) undersized emitters. The delta T is too high, indicating a flow problem. It may be that some additional emitters are needed. If this was new construction we would have added some. Why not fix the obvious stuff first.
  • smittyal06 smittyal06 @ 10:20 AM
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    What are the emitters that you speak of?
  • Chris Chris @ 9:04 AM
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    Not a Flow Problem

    There are not enough train cars attached to the train engine to carry the btu/hr required to drive through the R-Value of the floor and over come the heat loss!!!!! The btu/hr is being sucked up, used and abused! Plain and simple.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • Zman Zman @ 9:48 AM
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    Look at the picture on the post labeled "system" and please explain how it could possibly be working?
    I don't disagree that emitters could use improvement. I think the first problem is obvious piping errors should be addressed before tearing apart the house .
    High delta t indicates too much emitter for the flow or too little flow for the emitter.
  • smittyal06 smittyal06 @ 10:31 AM
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    Here is another photo. There is a pump sending the fluid through the electric boiler and the transfer plate. The electric boiler is turned off all season as we use the outdoor wood boiler.
  • Gordy Gordy @ 10:24 AM
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    Boiler piping

    And manifolds yes I agree its all lack luster. But at the same time you need to know if the emitters are going to work.....right?

    1/2" pipe feeding 2 3/4 loops is a red flag also. Unless those loops need less than 7500 btus each.
  • Tom Tom @ 1:02 PM
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    I realize the electric boiler is off when the wood boiler is on but the circ still pumps through it all the time. The boiler and the plate exchanger combined means a lot of restriction. But if you valved off the plate exchanger and still didn't get the heat I would say you have other problems. I don't like the non closely spaced tees separating the individual zones, the pump on the return after all the zones in respect to where the expansion tank is.
  • Gordy Gordy @ 7:26 PM
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    Boiler head loss

    That electro boiler has pretty low losses. Smitty can you verify size of boiler? Model #

    Also heat exchanger size (output) brand so we can calculate some head losses in the mechanical room.

    Also pump sizes/ brand.

    3/4" copper can carry 42000 btus. So you are right there for your heat loss.

    If the passengers (Btus) are all ready to board the train (boiler loop), and there are not enough seats, and track (radiant loop) to get them to their destination we have to redisgn.
    This post was edited by an admin on August 22, 2013 7:41 PM.
  • Rich Rich @ 9:54 PM
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    I concur Gordy

    Smitty if you owned the railroad and all the passengers that had to be at work at 8:30 took all the seats and got off at the first 3 stops out of a possible 12 stops you would add more seats for the people that had to be to work at 9:00 at the other 9 stops .
    You didn't get what you didn't pay for and it will never be what you thought it would
  • smittyal06 smittyal06 @ 8:06 PM
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    The electric boiler is a Electro-Boiler Model EB-MS-15.
    The heat exchanger is a SWEP B10THX20 / 1P-SC-S
    The 3 pumps feeding the floors of the house are Grundfos UPS 15-58FC and the Blue pump placed to the left of the electric boiler is a Grundfos UP 15-42F.

    I agree that more tubing needs to be added in order to provide better heat for the main level. My question still remains this. If I do this, will this leave more heat in the system for the upstairs? I know run on 16" centers the upstairs is not run properly either, however, I am not as willing to tear out the ceiling of the main level. So, would the remaining heat in the system be enough to heat the upstairs given the heat loss calculations and knowing there are only two loops upstairs run the same as the main level?
  • SWEI SWEI @ 7:55 PM
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    Room by Room Heat Loss

    will answer that question.
  • Gordy Gordy @ 9:08 PM
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    You did your heat loss calculations correctly. Then yes your boiler will produce the required btus to heat the home. You just need to have an efficient amount of emitter to transfer those btus where they need to go, and that's to each room.

    It does you no good to produce 51000 btus with only enough emitter to move 27000 btus. Gotta get them out of the mechanical room

    Think of a conveyer belt. With btus on it going to various parts of your home.
  • Gordy Gordy @ 7:35 PM
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    Your circs should be fine for the head they are pushing.

    When you were using the electro boiler what temps were you running?

    That's a three stage boiler. 51000 btu output.

    Definitely repipe the supply/return manifolds with manufactured ones with flow meters. In doing this think about how many more loops you will run, and get the proper size manifold accordingly.
    This post was edited by an admin on August 28, 2013 7:42 PM.
  • smittyal06 smittyal06 @ 6:54 PM
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    I know this is a very rough sketch. I have drawn the layout of new pex. I came up with 7 runs on the main level.
    Bedroom: 250'
    Living1: 250'
    Living2: 260'
    Bath: 290'
    Dining: 280'
    Kitchen/Laundry: 250'
    Kitchen2: 275'

    If you wouldn't mind taking a look at what I have.
    Is going with 1/2' pex the proper material to go with?
    This post was edited by an admin on September 2, 2013 6:55 PM.
  • Gordy Gordy @ 5:27 AM
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    New layout

    Smitty I assume you are leaving the 3/4 in place. These 3/4" loops will have to be repositioned to allow another run in each joist bay.

    Will you be using extruded omega style plates, on the new loops?

    Do the loop lengths you gave include leaders to the supply/return manifolds?

    1/2" pex will be fine. At .7 gpm flow rate your head will be about 5.2'. At .6 gpm it would be 3.8 ' of head.

    You still have to address what water temps you are using to calculate the proper flow rates.
    This post was edited by an admin on September 3, 2013 5:34 AM.
  • smittyal06 smittyal06 @ 8:47 AM
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    I was going to take down the 3/4 inch and start fresh so all of the loops would be 1/2". Would you recommend using the 3/4" still?
    I was not sure what plates to use. If that is what you recommend, that is what I will go with.
    The loop lengths do include leader to and from the manifold.
    I am not sure what you mean by head?
    The water temps I used in the past were 175 degrees. Would you recommend staying with this or could they be lowered?
  • Gordy Gordy @ 7:47 PM
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    Honestly I would start from scratch. You can  find decent manifolds for 3/4" pex with flow control valves, but decent extruded plates for 3/4" pex not.. This is why you have the plates they have.

    Its nice having flow control valves to dial in the flow rates you will know exactly what you are getting. Verses a pump curve, and unknown loop lengths you can get close.

    In the end as I said if you leave the 3/4" pex. The runs would have to be moved in each joist bay to allow for the extra 1/2" loop your installing to get 8" on center. So basically your taking everything down except where it loops through the joist, and moving it one way or the other.

    Using extruded plates will help lower water temps, and or increase output. Careful 180* is usually the limit for pex. The omega style plates grip the tubing better. (more contact area), and they are thicker (better heat transfer).

    Head is the resistance the circulator has to overcome to create flow. The smaller the Dia. of the tube creates more head, and the higher the flow rate creates more head, and the longer the loop length creates more head. Think like water its lazy, and dumb. You have to tell it where to go, and how to get there. The easier the path is for it to follow the less energy it takes to get it there.
    So keeping head loss reasonable helps you select a circulator as small, and energy efficient as reasonable to do the job. You have three 15-58's now YOu should be fine if your loop lengths are as you stated.
    This post was edited by an admin on September 3, 2013 7:52 PM.
  • smittyal06 smittyal06 @ 12:50 PM
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    Cost and Quality

    I know there are probably different qualities of pex pipe. The supplier I am working with will sell a 300ft roll for $172. However, Menards has a 300ft roll for $100. Is there going to be a major difference in going with the more expencsive stuff? Is Menards stuff junk and should not be used? Also the heat transfer plates. The picture I provided would these be good, or do you want one that wraps completely around the pipe? Does it matter if they are steel or alluminum? I have also got different opinions on plate placement. Should the transfer plates be butted up next to each other or a space between them? If a space, how much? Thanks.
  • Zman Zman @ 2:36 PM
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    You want to go with Pex-a with an O2 barrier or pex al pex
    I am suspicious of  stamped steel plates. Do you have test data on them?
    The last guy did this job cheap without a proper design. Do your homework so you do not follow him.
  • smittyal06 smittyal06 @ 4:32 PM
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    I would agree and that is why I am asking all of you. The Experts!
  • Zman Zman @ 6:00 PM
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    I realize that you are doing your research. I hope that did not come across wrong.
    There a many companies selling products based on fictitious claims. I would not buy those plates without some back up data.
    I realize that I am in the minority on this. I am still wondering if you have measured the delta t in your existing condition. Do you know the make and model of those mixing valves?
    I agree with all who are think you may not have enough emitters. Your high delta t tells me there is also a flow issue.
  • Tom Tom @ 6:11 PM
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    Zman is correct

    I really think the emitters are incorrect but the piping in the room is as bad if not worse.

    Smitty, where are you located?
  • smittyal06 smittyal06 @ 12:36 PM
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    By emmiters are you talking transfer plates? I am located in Northern WI.
  • smittyal06 smittyal06 @ 12:35 PM
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    You did not come across wrong at all. And I was serious when I mentioned I am asking the experts. I truly am taking everything you all provide to make this work.  I have removed all of the old piping and am ready to install new. That is why I am making sure now I am getting the correct piping and transfer plates.
    Are these the type of plates you would use? They are Omega Aluminum. 18"x5" Not sure on gauge. If not, does someone have a good source for good plates that I should purchase. And maybe a picture so I know exactly.
    This post was edited by an admin on September 13, 2013 12:38 PM.
  • Gordy Gordy @ 6:53 PM
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    steel plates

    Smitty those are garbage compared to extruded aluminum plates.

    Remember conduction is king with radiant heat. Extruded plates encompass 200 degrees of the tube for the plates total length. Now look at the steel ones. They encompass the tube 90 degrees intermitently for the plates length. Also aluminum is more conductive than steel.

    Conduction from the tube to the plate, and from the plate to the subloor gets the btus where they need to be. at lower water temps.
    This post was edited by an admin on September 12, 2013 6:54 PM.
  • Rich Rich @ 9:20 PM
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    Space between

    emission plates . Yes you should have a space between them . An inch is usually good . They will expand as anything that gets hot does , they should have room to do so without affecting adjacent plates or putting undue stress on tubing .
    You didn't get what you didn't pay for and it will never be what you thought it would
    This post was edited by an admin on September 12, 2013 9:21 PM.
  • Zman Zman @ 3:02 PM
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  • smittyal06 smittyal06 @ 4:05 PM
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    So these are better then the plates I pictured which completely surrond the tubing? Again, I am not questioning, just asking so I do it right. Does brand of tubing matter much as long as it has an oxygen barrier and is grade-a? I mean there are some that run $130 for a 300 ft roll or like the Wisbro Hepex from the same company that makes the Joist Trak runs $179 for a 300 ft roll. Is it worth going with the more expensice stuff?
    Thanks for that site!
    This post was edited by an admin on September 13, 2013 4:26 PM.
  • Zman Zman @ 5:42 PM
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    The safe move...

    The safe move is Uphoner/wirsbo hepex or pex-al-pex .
    The uphoner plates work much better than the "w" plates.
    There are other brands that are similar and are probably widely used.
    Uphoner is the leader and has stood the test of time.
  • smittyal06 smittyal06 @ 1:12 PM
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    The pex-al-pex is a grade b. Earlier it was mentioned that I should stick with grade a. Is the grade b stuff then okay to use?
    The hepex is about $179 for 300 ft coil and the Pex al pex I am looking at about $110 per 300 ft coil. Significant price difference if I can go with the al pex. I was reading thought it is hard to get fittings and they are more expensive for al pex? However, I don't believe i would need many fitting b/c it should just be hooking up to a manifold correct? So, can I or should I go with pex al pex?
    This post was edited by an admin on September 14, 2013 1:38 PM.
  • Zman Zman @ 7:11 PM
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     I had not realized the Wirsbo Multicor was pex b. I guess they need to do it that way to laminate it.
    The pex a ,b and c are not grades. It is the process used to make it. I am not saying all pex b products are bad. I just have great faith in pex a and wirsbo.
    This expains the process.

    This post was edited by an admin on September 15, 2013 8:55 AM.
  • BMET BMET @ 8:12 PM
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    Cold Baseboards

    I have a couple baseboards in my kitchen and one in particular i can find either the inlet or return. I'm not sure. Theres some kind of valve or something i can't identify but after that valve the pipe is cold. On the picture the right of the valve is cold.
  • SWEI SWEI @ 9:28 PM
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    Cold Baseboards

    Please start a new thread with this topic.  You will get more eyeballs on it and it will help avoid confusion. 
  • Gordy Gordy @ 10:16 PM
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    Balance valve

    That is and is in the open position . Air bound?
  • Zman Zman @ 9:08 AM
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    Which post??

    That is a new one time post on top of another.
  • jumper jumper @ 2:20 PM
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    three questions?

    My first question is what's the heat exchanger for?
    My second question is is your floor covered with carpets and furniture?
    My third question is what's the temperature of the floor?
    If your boiler produces sufficient output then your house has to warm up eventually.
    A big advantage of hydronic heating is that it's relatively easy to add terminals where needed. I'd look into adding ceiling radiation. It can make you more comfortable without making your home warmer.
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