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Wood floor stability over radiant floors

This is the first time I've seen you here. The guru of BTU's on vacation?

Mark have a chance to look at this one? The Glowcore™ has GOT to go but you allready know that. Right? The manual 4 way could be malfunctioning/stuck due to poor water quality ETC. Of course you could go with a motorized mizing valve and that would be best but, why spend the dollars to stabalize the floor emitter sub-system when the Glowcore (plant) will be giving out on you and your clients very soon and likely at the worst possible time of the year. 1 Re-build old four way valve, collect cash and leave. Tell clients to lose your Tel.# when things go wrong. 2 Install new motorzed mix valve (this ain't easy nor cheap to do) New system. You pick one. Ditch the buffer tank idea. Not sure why you would need to divert/slow down BTU's but there may be something you've left out.

Sleep well:-)

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  • Tom Olds
    Tom Olds Member Posts: 6
    Wood floor stability over radiant floors

    I recently saw an existing infloor system that had badly deformed wide plank(5")pine flooring in an isolated part of the house. Of course I initially assumed it was a moisture problem maybe the result of an errant staple but the owners had a professional out to verify that the wood did not have an excessively high moisture content. For good measure I shut off the makeup water to the system for several days and the pressure did not drop. Upon closer inspection I found a manifold for the area being served near the damaged floor. In the basement I found the system utilizes a Glowcore low mass boiler with a "manual" 4-way mixing valve. We turned that zone on and within about 5 minutes the supply temp to the floor already exceeded 125. My assumption is that excessive heat saturation has caused the floor to fail but only near the manifold. I'm curious if anyone else has seen this before. My strategy is to add motorized control with temperature limits on the 4-way valve and a buffer tank to add mass and prevent short-cycling during low load conditions. Because of the type of floor I know we're going to get some movement but I would expect far less incorporating these improvements. If anyone has any other ideas or thoughts I'd love to hear them. Thanks! TJO
  • Steve Ebels_3
    Steve Ebels_3 Member Posts: 1,290
    Actual floor temp?

    Did you run the system long enough to get a clear idea of what the floor temp actually was? Is this a staple up install and what is used for the under floor insulation?

    I agree that modulating water temps are THE ONLY way to go for good control!
  • Tim Doran
    Tim Doran Member Posts: 208
    Wood Floor thoughts

    I few years back I spent the better part of two weeks talking to wood floor manufacturers and installers to help me get a grip on this stuff. The long and short of it is that wood is hygroscopic and is easily influenced by moisture. Temperature alone does not typically cause a significant amount of movement. Temperature only helps to speed up or slow down the change in moisture content. Moisture must be present for wood to move.

    So even though the wood may have had an acceptable moisture content when it was checked by the wood floor pro, it must have had a higher moisture content at some point. Did the wood cup or bow? Cupping is when the edges roll up and bowing is when the edges roll down. Was it slab sawn or quarter sawn? What is under it? Can you post pictures.
  • Andrew Hagen (ALH)
    Andrew Hagen (ALH) Member Posts: 165
    Sounds like a good time

    to replace that boiler with a modulating, condensing model and get rid of the 4-way altogether ;-)

    An HK Universal mounted on a new 4-way would be nice, but it's cost is half way to that of a new condensing boiler.

    Definitely want to make absolutely sure there are no leaks. It could be a very slow leak.

  • John Reed
    John Reed Member Posts: 5
    wood floor stability

    Tom, I do not profess to be a wood floor expert, but have done a few underfloor staple-ups with transfer plates, and have also done quite a few wood floor installs. First, I would never sell a staple-up to someone who will not let me install automatic 4 way, I also like to do outdoor resets( Iam a Buderus fan, and love to do these with their 2107's)So far, I have been able to do these jobs, and never have to exceed a supply water temp over 110-112 degrees. Now the wood: pine, especially wide boards, has got to be one of the worst choices for radiant jobs, way to unstable to changing conditions. It also can become extremely unstable if exposed to high moisture levels. I would suspect that at some time, that floor saw an extremely high moisture level. I can show you 3.25" wide oak flooring that cupped, and never returned to its original state once exposed to high level of moisture, and oak is relatively more stable than pine. The high water temp will more than likely dry the pine to the point of it wanting to split like crazy.That is another downfall to doing mediocre staple-ups and not properly controlling water temp.Just my opinion, and two cents worth.
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