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    Hydronicly Challenged (13 Posts)

  • Zeffern_Cochrane Zeffern_Cochrane @ 12:26 AM
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    Hydronicly Challenged

    Hey I'm yet another guy trying to do it all my self. My father was a mechanical engineer who specialized in heating and cooling and gave me some initial ideas on how to set up my system. Unfortunately he passed away a couple months ago and now I am trying to honour my commitmitment to him that I would get some professional help to bring my system online.

    That being said I have taken my house plans into the local plumbing supply place who is doing a lot of design work for me so I know I have the right size boiler ect. I all ready have the basement 6" slab poured with 8 250' loops spread over 2500 sq. ft. The slab is on top of 2" of rigid styro insulation. and the basement walls are the ICF blocks with about 3" on each side being styrofoam and 8" concrete. I have 5 windows 36" X 48" in the basement At the time I was told by the supplier that it was about an R-40 rating, the height of the basement is 8' 6" and only has about 3' above grade. At the time I put in the loops my father did some calculations and advised me to run 4 loops around the outside working in so I pretty much have one for each side of the building the first two runs are 12" on center and the remainder is on 18" centers. My father advised me that would be enough. (I live in the prairies of Canada about the 54th parallel.) Now that I have seen the pro who is helping me he advises that in actuality the ICF blocks are really only about R-22 (I find that hard to believe because styrofoam SM is R-5/inch and I have 6" of the stuff.) And that I do not have enough heat lines in my basement.

    Anyways I said all this because I am questioning a few things he has advised for my main floor. Some areas of the house have a 9' 8" ceiling and a few windows and he is advising that I will have a shortfall on my ability to transfer enough heat from the floor for my heating. And that I will in addition to the radiant floor heating have to install additional sources of heat, be it radiators or heat coils. I have my sub floor designed to hold a 2" concrete slab and plan on placing the heat lines at 6-12 inches (What ever is required) then pouring and finishing the concrete as the final floor no tile or wood on top and only a few area rugs. (Wife has allergies) Something just does not seem right I advised that I would have standard R-20 walls and R-50 for the ceiling. I can not beleive that I will not be able to get enough heat into the spaces where I have limited windows. In the main open area of the living room I have a14' high vaulted ceiling and lots of windows. (there I could accept that there could be a problem but not in the bedrooms and bathrooms where I have limited windows and a lower ceiling. His calculations for the house showed 160,000 Btu mine on the internet joe newbi came up about 20,000 less.

    Another thing I wonder about in his quote was that he advises a fancy control box with mixing valves and zone pumps for every zone then goes one further specifying those fancy manifolds with balancing valves and flow meters on every loop (to date and for future loops I intend to make them all 230-250' each as the oxyPEXpipe come in 250' lenghts so it's pretty easy to keep them even. I was thinking that a more economical system would have 1 or 2 different primary and secondary loops reducing the temperature to the required (I would think 100F or something like that) then zone pumps for each area of the home 1 for the basement, 1 for the living room 1 for the bedrooms ect. ect. would suffice. I would be most interested in what some of you other professionals would suggest


    So a few questions but really I am looking for any imput or your feelings on what I have said. I do have 2 direct questions.

    1) Why after reading the story about Dan going to the church for so many years did he not do something to help the situation :) (Perhaps give some advice to people in similar circumstance.) And I mean advice on the making the heating more livable not the good advice he gave on not committing to solve all the churches problems.

    2) Why would you want to have $300.00 12 port manifolds when you could build them out of copper ones and some 1/4 turn valves for about $100.00


    Thanks In advance.
  • STEVEusaPA STEVEusaPA @ 9:51 AM
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    Some thoughts

    1. I would never speak for Dan, but in those types of situations, you end up owning the entire problem, and end up working for free, and you'll always be on the hook for anything that goes wrong after that.

    2. I would always pick the manifolds with the flow meters. Unless you need practice soldering, the additional $200 would easily be eaten up by labor, 75-plus solder joints for each supply/return, etc.

    Some other points
    1. how was the heat loss calculated?
    2. Can you post pics/diagrams of your plans, you'll get more opinions. The reason why I say this, is you sound super insulated, with large rooms, you should definitely have enough floor space for the btu requirements. The higher, well insulated ceilings arent a propblem with the radiant heat.
    3. If I was in your shoes, depending on your location, I would submit the plans to someone who specializes in radiant heat. The few bucks you spend now will be well worth preventing future long term problems. There are some great people here, who are up to date with the latest equipment, practical experience far superior to a supply house, Some supply houses may steer you towards products they sell, and ways they 'always did it'.
    Some of the top dogs I would trust in a heartbeat are
    Mark Eatherton
    Rob @ NRT
    Ironman Bob Boan
    and many others.
    Just search related posts and you you'll see (read) their expertise.
    steve
  • Paul Pollets Paul Pollets @ 10:29 AM
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    Design

    If the wholesaler doing the heat calcs uses the proper software, they should be able to tell you everything about the project, including balancing charts for the manifolds and correct pump sizing. The program also does a "what if" in regards to loop spacing and water temp requirements. The Uponor ADS program will flag the room if it requires supplemental heat. I've never seen a residence under 5K SF with a 160K btu heatloss. Even in Alaska. I'd make sure the wholesaler was using the proper radiant design software. Unless the software is radiant specific, you'll never get the correct heatloss.

    I'd only use manifolds with balancing ports. Since all of your loop lengths are similar, balancing shouldn't be an issue. Many prefer having separate loop(s) for each room which tells me your design is by area, rather than room.
  • Zeffern_Cochrane Zeffern_Cochrane @ 11:04 PM
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    more details

    In my area R20 for walls and R40 for roofs is the minimum so I would not conceder my new home super insulated. I would though conceder it to be very well sealed as I am taking all possible precautions to make sure the vapour barrier and around windows and doors is as good as it can be.

    His calculations were actually 154,000 for the house he specified a 199,000 Lochinvar Knight Boiler. He may of upped the BTUs based on my initial request to have an indirect hot water tank and the ability to heat a 4 person hot tub. I have now looked a bit more into things and was thinking I could save a few bucks by going with an NY Thermal Trinity TI200C combi boiler unit and skip the indirect tank. it is 181,000 the tank he specified is 80Gal. (that seems a little big to me) It is just the wife and I but should conceder that the house may one day (Far from now) be sold to a family. I have a copper heat recover coil installed on the main drain. I think that would work great in combination with on demand hot water. Though after some correspondence with the design guy I am left with the impression i am really selling myself short by going with the on demand Trinity boiler.

    I saw the heat recovery coil on some GREEN tv show and though what a great idea so I tracked down the supplier and bought it. Also at that time asked for quotes on designing my heating system. He said $1400 for the heating including loop layout plans and $1400 for the HRV design. I though that a bit steep and now am glad I did not go with that as this second fellow says I can get away with a 64-146CFM HRV system. All in that would cost about as much as the quote from the first guy to design plans for it. And apparently duct work is so simple it will not be a problem for me to do that on my own. Just put a vent in each room.

    The supply house of course only specifies products that they sell and the only cost I would incur is if I wanted the loop layout plan for a charge of $500

    What would be a reasonable price to pay for independent design consultation and service?

    I am pretty certain that when it is all said and done I will end up getting a local plumber who does a lot of radiant work in my area to help out a bit especially with gas lines and sizing them as well as commissioning the system.

    Manifolds:
    I built up a coupe from the copper pex plumbing ones using 1/4 turn valves and joining them to the manifolds with a 2" piece of Pex. I though they looked pretty slick and did not take me long to build. Would there be anything wrong with using one like this on each end of the loops?

    Thanks
  • copperkid copperkid @ 10:18 PM
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    Manifolds

    I know you don't have a T-drill, this is specifically made for doing branch tie-ins on copper. You can take a step drill or unibit and drill the ports in a piece of 1", 1 1/4", or larger.  Just drill a 5/8" hole and put a stub piece of copper tube barely in the inside and use 15% brazing rod, we use Sil-foss or Harris and braze 'em up.  Otherwise you can buy the copper manifolds with or with out valves for less than 100 bucks.  I'm making my own, just because I have the materials left over from previous jobs. 
  • copperkid copperkid @ 10:18 PM
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    Manifolds

    I know you don't have a T-drill, this is specifically made for doing branch tie-ins on copper. You can take a step drill or unibit and drill the ports in a piece of 1", 1 1/4", or larger.  Just drill a 5/8" hole and put a stub piece of copper tube barely in the inside and use 15% brazing rod, we use Sil-foss or Harris and braze 'em up.  Otherwise you can buy the copper manifolds with or with out valves for less than 100 bucks.  I'm making my own, just because I have the materials left over from previous jobs. 
  • Zeffern_Cochrane Zeffern_Cochrane @ 11:10 PM
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    those plans

    A few things to mention on the plans there is a seperate enclosed deck on the back of the house that is not included in the heating calculations but would probably end up being heated perhaps that is why he sized the boiler as he did. The last page of the plans have window and door sizes on them all the windows are dbl pane and mostly crank out design only a few sliders on the main floor. in the basement there are 5 sliders 36 X 48"
  • zacmobile zacmobile @ 4:46 PM
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    ICF R-value

    I just wanted to pipe in on the R-value of ICF walls. Your pro who advised you that your walls are only R-22 is wrong. If you have a good heatloss program you can calculate the R-factor of different wall assemblies and they take into account the lack of thermal bridging in ICF construction, a big factor in conventional stick frame construction. You probably are close to R-40.

    I also live above the 49th parallel and I can tell you from personal experience that my radiant slab in my ICF basement requires very little temperature & flowrate and I have a significant amount of windows & tubing is 9" centres. Even with the slab off it mantains 17C in the winter.

    Your tubing spacing is abnormally wide, the minimum I would ever do in any circumstance is 12" but my gut tells me you will probably be all right.
    This post was edited by an admin on April 4, 2013 4:49 PM.
  • Zeffern_Cochrane Zeffern_Cochrane @ 6:54 PM
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    Spacing in basement

    Thanks I too am confident that the spacing is satisfactory to get enough heat into the area as my dad was always on top of his game when he did his engineering.

    I asked the heating guy to recalculate using R30 for the walls and R60 for the ceiling on the main floor and he said it reduced my shortfall from 31,000 to 29,000. Something just does not seem right.

    Can anyone suggest good internet calculator the one I know of only goes to R20 for walls and R40 for ceilings, or good software for this. How is this Taco Flo Pro stuff that Dan provides a link to ?
  • Zeffern_Cochrane Zeffern_Cochrane @ 10:33 PM
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    Heat Loss Calculator .XLS

    Well I guess I found one or maybe something better it is an XL format of an unprotected spreadsheet that this Dick Moore fellow was nice enough to put up online. I did a work through of my plans and came up with 67,000 BTU/hr on the main floor. And 26,000 in the basement. Bumping my insulation to R28 in the walls and R60 in the ceiling.

    I was a bit sketchy on the basement as to what temp to use for the outside I used R40 walls and gave it the top 3' the -40 coldest outside temperature that it would see. I used 3 feet because that is what is exposed above grade. I calculated the next 3 feet below grade at 0 degrees and the bottom 3 feet to the footing at 40 degrees.

    I would surely appreciate any feedback from some of you experienced folk as to the validity of my results or the spread sheet.

    Thanks


    For anyone interested the XL file is attached in that file is the address of where the file was found online and the instructions/explanations.

    Hmm pitty seems this site lacks the ability to upload XL files here is a link to the page.

    http://www.moorepage.net/heatloss/heat-gain.jpg
    This post was edited by an admin on April 4, 2013 10:35 PM.
  • zacmobile zacmobile @ 3:47 PM
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    gain

    Err, it looks like that link is a heat GAIN calculation, the inverse of a heat LOSS calculation. Do you have a link to the heat loss calc?
  • Zeffern_Cochrane Zeffern_Cochrane @ 6:10 PM
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    Heat Loss Calculator .XLS LINK

    Yes sorry actually I discovered afterwards that in fact that is almost the right address the actual address will take you to a web page that will give you both heat loss and heat gain calculators.

    http://www.moorepages.net/heatloss.html
  • Gordy Gordy @ 11:31 PM
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    D

    This post was edited by an admin on April 5, 2013 5:59 AM.
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