On Sunday, July 1, 2012 4:59:39 PM UTC-4, George wrote:
On 7/1/2012 3:16 PM, Bob F wrote:
Evan wrote:
On Jul 1, 12:36 pm, JIMMIE wrote:
Recently my HVAC compressor unit was stolen form a vacation home,
soon to be permanent residence. I was thinking about upgrading to
geothermal given that there are already 2 400 ft water wells on the
property. I am trying to find some meaningful info but so far all I
can find is sales pitches even when talking to an installer. Current
HVAC was a 4 ton heat pump about 5 years old. Air handler is still
in good condition. I am looking for info that will let me know
whether or not I can use the wells and/ or the existing air handler.

TIA
Jimmie

Your two wells are nice and all but a ground source geothermal
system is typically spread out over a larger area with coiled
loops of tubing which are buried (larger ground contact area)
rather than narrow wells with limited ground contact area...

Geothernal heat pumps can use water sources from wells, lakes, streams, or
buried tubes. The limting factor would be the volume and temperature of the
supplied water. Buried tubes are only one possibility. They may be more common,
but that is just because that is simpler for most sites.

The well provides way more ground contact area in many cases, since it accesses
a significant area of the water table. They do require a significant volume of
well water. (Remember - two wells - water from one, going to the other)



A friend had one installed last year. We thought they were going to do
as you described. They actually drilled a couple wells and dropped a
loop of tubing into each well. So his "side" is actually a closed loop.

The closed loop system was what I was aiming for although I had considered pumping water well to well. Usually there is at least 300 ft of water in the wells. Information is a little hard to come by. Conceptually this doent seem like it should be much more complicated than a regular heat pump with the air to freon heat exchanger replace with a liquid to freon heat exchanger and replacing the fan with a circulating pump. How far off base am I? Would I need multiple loops in the wells or just one. What type of pipe is used to make the loops in a vertical system.

30 years ago I saw a home brewed system. The guy made his own water to refrigerant heat exchanger by passing water through every third turn of a regular air to freon device. He was fortunate to have an artisan well on his catfish farm for a water supply. This design also allowed him to use the fan on the outside coils if needed.

Jimmie