# Dehumidifier idea



## fishhead (Jul 19, 2006)

This isn't an alternative energy idea but it is an energy saver.

Someone just asked about dehumidifiers on another forum. At the same time another person is having condensation problems from incoming well water.

Why not use the cold water to condense the moisture out of the air in a more controlled way? I'm thinking a person could run the cold water into a tank or radiator and then use a small fan to push the warm humid air over the surfaces.

Does anyone have any simple plans for a dehumidifier that uses cold well water instead of an energy hog compressor?


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## greif (May 31, 2009)

yes but I think you would need a lot of water


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## fishhead (Jul 19, 2006)

I'm very conservative with water usage but I still filled up a 2,750 gallon septic tank in about 4 months and that was without the washing machine. That's about 25 gallons a day. I think the average person uses 100+ gallons/day so there's at least 830 lbs of 50 degree water.


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## TnAndy (Sep 15, 2005)

You also have to come up with an efficient heat exchanger, but, yes, it will work to a degree.

I have a dry kiln in a room built in my shop. For some extra drying, I experimented with something along the lines you propose. There is a creek right behind the shop wall where the kiln is located. I ran a 1/2" line from the creek into the kiln, then into a car oil cooler, then back out into the creek, dumping the slightly heated water. Put a drip pan under the heat exchanger to catch water as it dripped off. Worked pretty good in the winter when the creek runs good and the water is cold.

But the air temp in the kiln is 130 degrees, and the humidity level is 100%, where that wouldn't be the case in a normal basement...my guess is the efficiency would go way down.


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## fishhead (Jul 19, 2006)

Our well water runs about 48-50 degrees. My basement runs around 60 all summer. The well pipe has beaded water on it with no real air movement.

I wonder where a person could get a radiator that could be used with drinking water? I know in states like FL they use groundwater run through something like I'm proposing as their air conditioner so there must be some off the shelf parts somewhere.


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## TnAndy (Sep 15, 2005)

Yes, they make dandy water to air heat exchangers that go in the ductwork of system when someone connects one of those "out in the yard" water stoves to a house that has a forced air heating system. Buddy of mine in MD put one in his house.....looked like a copper pipe with aluminum fin deal...about 20" square, fit right in the duct above the blower fan. I'm sure it would be fine for potable water. Just not sure you would get enough dehumidification to justify the cost of install, since you won't have water running continuous thru it.


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## fishhead (Jul 19, 2006)

I think a person would have to rig up a tempering tank just before the water heater. Then put a circulating pump in the tempering tank so that it circulates that water through exchanger. Maybe put a thermostat on the circulating pump that turns on only when the tank is below the dew point.


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