Saskatchewan System Design

Discussion in 'General Discussions' started by BatocheBob, Dec 18, 2014.

  1. BatocheBob

    BatocheBob Member

    I have two geothermal systems to heat and cool approx 5,000 sq. ft. I am generally happy with the system but often wonder if it could be better. I have browsed this forum extensively both for advice and just plain old knowledge. A couple of things I have learned from this forum, and from my own experience, is that good design is crucial and that there is a significant difference between a conventional heating pro and one who specializes in geothermal heat.

    Having said that, when it comes to radiant over-floor heat there are several ways this can be accomplished. One method utilizes PEX tubing with metal conductor plates. There are two systems that I am aware of; Uponor Quik Trak and Eagle Mountain Radiant Max. The Uponor system has the metal plates under the furring strips while Radiant Max has the plates over the furring strips. I am wondering which system is more efficient. It seems to me it would be more efficient to have the conductor plates as close as possible to your flooring. On the other hand I recall a comment, I believe it was from Mark Curtis, that said a consumer sees insulation while a 'wethead' sees thermal mass.

    Is the Uponor system better because it provides more thermal mass or is it the 'lesser' system because there is more insulation? :)
     
  2. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    One always wants insulation in a radiant panel. The heat is going to take the path that is easiest.

    Mark
     
  3. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    Eagle MT. is more of a reseller. One of the guys here had a tutorial on building your own aluminum panels for the doityourselfer. Radiant designs #what works best varies from job to job.
     
  4. FryDaddy

    FryDaddy New Member

    In our home built in 2006 we used WarmBoard. This is what I would call no mass but reacts to change very quickly. These 4x8 panels are the subfloor and have grooves pressed in an aluminum sheet for the PEX. I have R30 under the WarmBoard and it is amazing how much heat gets radiated down. I have 3/8 inch quartersawn oak on top for most of the area right on top of the aluminum sheet. So this system has the plate right under the flooring.
     
  5. BatocheBob

    BatocheBob Member

    Thanks for the replies to date. I guess my lack of articulation is showing up again.

    Mark, I appreciate the value of insulation, especially where it will direct heat upwards through the thermal mass to the area where it's wanted.

    FryDaddy, I appreciate the reference to WarmBoard. I still have some area in the basement that I want to finish. The hydronic heat is embedded in the concrete slab but the WarmBoard may be an option for subflooring in the finished areas; I'll check it out.

    Joe, I went back and looked and the quote I used about 'Wetheads' was yours from Dec. 27/12 not Mark. In that thread the concern was about having too much insulating wood between the tubing and the room. My question in this thread was the difference between QuikTrak and RadiantMax. Both products use metal conductor plates around the PEX tubing. Uponar has furring plates between the conductor plate and the finished flooring while Eagle Mt. has their furring strips beneath the conductor plates. Eagle Mt. looks like the more efficient product to me but I brought up your quote because maybe the furring plates between the conductor plates and the finished flooring constitutes additional thermal mass and therefore beneficial.

    My next concern would be that for a given area to be heated by water if the Thermal Mass is increased wouldn't the water temperature or flow have to increase or maybe both? Thanks
     
  6. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    The purpose of a radiant system is that it looses heat to the conditioned space, and does not store it so it responds faster. Thermal mass is the enemy in the heat delivery system, you want thermal mass in the building but not in your radiators. That way they respond quicker to changing loads.

    here is a pretty good study comparing different systems, the differences can be dramatic

    http://scholar.lib.vt.edu/theses/av...e_Test_Protocol_for_Radiant_Floor_Heating.pdf
     
  7. BatocheBob

    BatocheBob Member

    Thanks Doc, what you said kinda supported my way of thinking. I was confused when the author of the thread I was reading was concerned about introducing a lot of insulating material between his heating tubes and the room. It sounded like the pros responding to that thread where discounting the concern and suggesting that the material should be looked at as thermal mass. maybe i interpreted the comments incorrectly.

    This leads me back to thinking that as above floor systems go, the Eagle Mountain system would be better than Uponor because it puts the heat from the tubing closest to the heated area.

    Thanks for the article. Pretty heavy stuff but I'll look at it closer and see what I can learn.
     
  8. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    Bob:

    Since I can not see doc any-longer I can not see his reference, One either has time or money.

    Is this a DIY?

    The more tubing one can put in a radiant panel the lower the supply temps can be to the delivery system. The lower the delivery temps the better a heat pump works. I am a member of the RPA, now part of the code guys. I say radiant panel not floor, because radiant is not limited to floors.

    I have no issue with the folks that build stuff to do radiant panels, but there are less expensive ways to skin the moose.

    My favorite way to do panels is "free form". Pack the tubing where the heat will be needed, doors windows, outside walls.

    Do you own a table saw?

    Mark
     
  9. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    Tried to look up the reference you offered and could not find it or context.
    A light crete floor can have some thermal mass for instance that will give up heat more slowly to a room then say a radiant panel but also cool more slowly. That's not necessarily a bad thing. It all depends on other features of the design.
    What are you putting over the top of this?
     
  10. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Google: DEVELOPMENT AND DEMONSTRATION OF A PERFORMANCE TEST PROTOCOL FOR RADIANT FLOOR HEATING SYSTEMS
    Author:
    Amit Khanna

    I really like the floor to be quick responding, you can always keep the flow running if you don't want them to cool down quickly, especially with variable flow pumps and outdoor resets, the zones call for much longer and have much more even heat. But it is tough to shut them off when you have to.
     
  11. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    Neat report doc. doesn't favor gyp crete for eveness. I'm still trying to get the context of my using the term "wet heads".
     
  12. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Yep, it surprised me too, but I could not find much in their methodology to question their findings. Sometimes you get surprised when you actually test your thinking.

    Science most of the time is not about answering questions, it is about questioning answers.
     
  13. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    The only thing I would offer is comfort and efficiency are sometimes at odds. Some clients have fwa and heated floors caring little if the floors heat the space.
    I'm working on such a job now.
    (Not that even floor temps wouldn't be better)
     

Share This Page