house burned up but closed loop is still intact, can I reuse?

[dforster2]

We had a 5 year old Climate master system with a 4 and 3 ton unit and I think 4 vertical closed loop wells. all of the piping in the house burned but the plastic stubs are still sitting above the ground outside. when they installed them there was also about 50 feet of horizontal to get to the wells so there is probabaly plenty of piping to dig up and tie back into.

I called a contractor and he said it should be ok to reuse the existing wells on a new ground source heat pump. One other question I had was that it was sized for 7 tons so I think they installed about 2500 feet of vertical loop. We are building a much smaller house and will only need a single 4 ton unit, if they use the entire loop will it make it more efficient or less since it will have quite a bit of pumping energy for the 2500 feet of loop? At some point the additional loop will not provide any additional heat exchange benefit so it will just be wasted pumping energy..

thanks for any ideas.

[SkyHeating]

I can't see why you couldn't reuse them. Just reconnect into the pipe and flush out any possible contaminants. As for the loop being sized for a 7 ton and house now only need a 4 ton, we would need a lot more information on the loop to come up with those calculations. There certainly is a happy medium between extra heat transfer and extra pumping costs. I would look at a variable speed pump as they use about 30% of the energy of a standard pump and would be your best bet on keeping the whole loop and getting the benefit from a 7 ton loop without the cost of pumping a 7 ton loop. As long as there is not a lot of head pressure the extra borehole or two really shouldn't cost you more.

[James Colver]

I can't see why you couldn't reuse them. Just reconnect into the pipe and flush out any possible contaminants. As for the loop being sized for a 7 ton and house now only need a 4 ton, we would need a lot more information on the loop to come up with those calculations. There certainly is a happy medium between extra heat transfer and extra pumping costs. I would look at a variable speed pump as they use about 30% of the energy of a standard pump and would be your best bet on keeping the whole loop and getting the benefit from a 7 ton loop without the cost of pumping a 7 ton loop. As long as there is not a lot of head pressure the extra borehole or two really shouldn't cost you more.

x2, it won't be a problem to have a larger coil in the earth, but make sure not to size your geothermal unit properly. I work on these all the time and if you size the equipment too large your house will be too loud.

[NickFisher]

I can't see why you couldn't reuse them. Just reconnect into the pipe and flush out any possible contaminants. As for the loop being sized for a 7 ton and house now only need a 4 ton, we would need a lot more information on the loop to come up with those calculations. There certainly is a happy medium between extra heat transfer and extra pumping costs. I would look at a variable speed pump as they use about 30%