# Radiant Floor Cooling?



## Mallow (Aug 4, 2006)

So we are finally getting city water to our house and we can now use the spring water for more things. As some of you may remember we live in an earth bermed passive solar house with radiant floor heating throughout. We also have a spring that runs all year that we were using for our main source of water with a well backup. Now that we have city water I was thinking of pumping the spring water through the radiant floor system then back to the holding tank. The current system is this:

220v Deep well submersible pump
House with radiant floor is about 100 ft higher in elevation.
I have a conduit so I can run a return line back down to the spring box which is about 1000 gallons.

Has anyone done something similar? I know I have to watch out for dew settling if it is humid inside. Currently the deep well pump uses a good bit of energy. Would it go down since gravity will also be pulling it back down to the spring box? Or should I look for another pump? Is a submersible deep well pump really made for continuous duty?

Thanks for any suggestions,
-Mallow


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## Bearfootfarm (Jul 13, 2006)

I doubt it would be worth the effort since heat rises.

You'd only be cooling the air at floor level if it even did that, and the transfer of heat to the water won't be enough to make a difference.

If you did it, I believe it would be most efficient to use a small pump for the circulation. The water would have to move slowly enough to pick up heat.

To get efficient cooling, you'd need to pass the water and the air through a radiator-like structure (heat exchanger) on the walls or ceiling so the cool air would flow downward.

As you already stated, condensation could be a big problem.
Maybe you could rig up something that sits outside the house, and use a fan to pass air through a heat exchanger to recirculate air from inside, much in the same way an air conditioner would do.


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## Mallow (Aug 4, 2006)

Thanks for the reply. I know it probably wont be the most efficient but I don't really like the small Window AC we are using now to cool the entire house. Would a smaller circulation pump work since there is a lift of 100' or so? Really for testing it, I would be out some black poly pipe and some plumbing fittings. If it cools sufficiently I would have to look at a better pumping solution. It may not work the best but still probably more efficient than the window AC unit.


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## haypoint (Oct 4, 2006)

You should be able to pull the floor temperatures down near 55 degrees F. Nothing like bare feet on a cold surface to cool you down. Condensation will allow the moisture in the air to condense and make the floor wet, study dew points. Ahhh... cold, wet, slippery floors.
There is no way for the cool floor to convect the cool air up to the living areas, away from the floor. Doesn't work like heat.
A water to air heat exchange would work a tiny bit. Many wood fired boilers employ a water to air heat exchanger. But they take 120-180 degree water to create 80 to 90 degree air. With your spring water at about 48 to 55 degrees, the best you can hope for is 30 to 40 degree difference, blowing 80 degree air in a 90 degree house. Plus running a blower and water pump 24/7.
In dry climates they use a swamp cooler that I know nothing about.


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## Bearfootfarm (Jul 13, 2006)

Mallow said:


> Would a smaller circulation pump work since there is a lift of 100' or so?


I doubt it.
You'd need a tank near the house with the small pump close by.
I can't see it being efficient enough to be worth the effort.
It works for heating by both convection and radiant heat, but for cooling you won't be getting any radiation.



Mallow said:


> It may not work the best but still probably more efficient than the window AC unit.


I really doubt it would be any more efficient, especially if your AC is less than 10 years old. 

I'd invest the money in a new AC before I'd spend anything for the in floor cooling.


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## Murby (May 24, 2016)

Trying to cool a room by cooling a concrete floor would result in a massive amount of condensation on the floor and fast mold growth due to the increase in moisture. 

This is a very problematic idea. 

You would be far better off passing through a proper AC evaporator coil that has a built in condensate drain, then go into the floor.. as a side benefit, the ac evaporator coil could double as a heating coil..


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