# A big hole...

Discussion in 'General Discussions' started by Guest, Jul 11, 2008.

1. ### GuestGuest

Hi everyone,
Newbie here, first post, apologies for anything overly dumb I am about to ask!

We are in central TX and have been interested in Geothermal AC for sometime, and the most common type round here seems to be the ones using a water well.

Anyhow on our land was an unfinished excavation for a large swimming pool. We dont want the pool. and intend to fill it in, and I just wondered is there any possible goethermal use for it? The hole is square, 20X40ft and 7 ft deep (perhaps as deep as 9 ft). Would that hole with tubing down the bottom be of any use for AC at all? We wondered if it might be worth it even if it only tries to cool a small guest house (1000 sq ft)

I realise that filling the hole with water as a pond might be better, but that is not an option for us, it must be filled in..

Any help MUCH appreciated, we intend to start filling it in this fall..
Cheers,
Gman

2. ### TechGromitMember

It might be big enough for a 1 ton Geothermal unit by installing the closed loop in three rows in the space provided, I'm not sure how far a 1 ton unit will get you, all depends on the heat loss of the house. Why not use the pool hole and add additional trenches to make enough to do the entire house.

3. ### GuestGuest

This is just for a very occasionally used guest house, but for interests sake, how deep a trench is needed in central TX? I havent ever seen a rocksaw that goes deeper than 4ft that one can rent, and if we need to bring someone in, it probably isnt worth the cost for a guest hse.. we just dont want to waste the hole, could it perhaps piggyback with a conventional ac sys just to help it a bit?

4. ### TechGromitMember

Generally the Trenches are 6 to 8 feet deep. I guess for the purposes of running the line from the house to the loop is could be as shallow as 4 feet.

As far as just installing a 1 ton unit to "help/assist" a standard air conditioning system, it's not going to be worth the investment. I say your trenches for a closed loops system are going to be one of the least expensive items on a Geothermal system install. If your going to invest in a geothermal system, your better off adding the trenches you need and install a system large enough to heat/cool the whole house. A big hole in the ground really isn't going to save you all that much in the whole scheme of things.