i have loked and read about geo-thermal (means i don't know jack). but i thought goverment was trying to discourge the pump out and pump back in the ground system. been to a few home shows where the push closed loop systems and the major cost seems to be inground installing of the tubes. which an engineer has to figure the delta formula to know length of run (FM, friggin magic
). any way why can't somebody come up with a way to use your existing coils and put it in a tub then circulate your gound source coolant. i left that vague but can you see where i am going?