Ideas For Geothermal Drinking Fountain

[Tudorman]

I want to put a drinking fountain out by the swimming pool come spring. I could put one of those little plastic deals that hooks to the outside hose bib, but nobody wants to drink warm water on a hot summer day. A commercial refridgerated jobber cost to much to buy and run. Besides, what fun are those?

So I'm thinking of digging a hole, at least four feet deep, six would probably be better, and burying some pipe to act as a heat exchanger. (Plumbed to the domestic water, of course.) I figure that deep the ground is always near 50 degrees, which I think would be cold enough to refresh. (Northeast Ohio) Bring it up out of the ground into a drinking bubbler.

I'm looking for some opinions to optimize the design:

1. Small diameter pipe/tubing to maximize surface area and therefore heat exchange? Coil it up? How long to make it?
2. Instead of the coil, use a large diameter (4") reservoir to hold the chilled water. What length? I figure a drink of water would average 6-8 ounces.
3. Copper or PVC or PEX pipe? All are easy enough to work with, and for a project this small, even copper would not be cost prohibitive.

A stupid little project, for sure. But it would be cool (pun intended) to have nice cool water out by the pool on demand.

 

[Jags]

For a 6 oz. drink of water, wouldn't the buried pipe contain enough water on its own (like using half inch copper, or what ever)? Copper, being a pretty good conductor of heat, should "recharge" the new water pretty quickly.

 

[karri0n]

Not sure why, but I've lived in houses with well water as well as those with city water, and even in the hottest summer days, the water from my outdoor hose faucet has always been blisteringly cold.


Your idea seems pretty sound. I say go for it. However, I'm with jags in thinking that the pipe should be sufficient.

 

[Tudorman]

From the foundation to the bubbler will be about 35 feet. If I could bury the pipe 5+ feet along this entire length, no worries. But that would be hard to do by hand, and it would take a pretty big trencher (rented, of course) to bring onto my lawn. So I figured the next best option would be to run the line 18" or so deep to the bubbler location and the stick the heat exchanger there. A 2' diameter hole 5+ feet deep is doable by hand.

I was mulling this further today. I think I'll try running a small diameter heat exchanger into a reservoir. This will provide a supply of cool water for those times there are lots of kids over (I've got four myself).

Does anybody know if PVC gives water a funny taste, especially if the water has been sitting in it?

 

[xpertpc]

I'd use one piece of pex, pe, or copper so as not to have any joints that could leak, never use white pvc for drinking only for waste, you can however use cpvc.

I just noticed you're in Ohio, I'd use pex or pe because it resists freeze breaks the others would likely crack even if vented and water was still laying in it. Water doesn't freeze uniformly in pipes and can form a bulge.

 

[Duetech]

To prevent freezing use a hydrant like you get at TSC. That way you can leave it un-attended and don't have to worry about freezing. When turned off at the hydrant the water drains out so it can't freeze. Just bury the line below the frost line and surrounded in sand.