30 Plate Water to Water Heat Exchanger 3x8 | eBay think more like this.. a flat plate exchanger made to soldier right into an out of your unit. I agree with some of the other comments about not putting the water back into your well. Suggest a dry well where you can drop the water back into your yard that is atleast 6 feet or more in depth... Direct (x) exchange to the ground is another option ... in some ways easier.. You can do this with four small bore holes that go perhaps 50 feet in depth.. Direct x you will in essence be adding tubing in and then out of each bore hole and they become an extended fin to exchange heat with the ground. So you will be using the pump in the compressor and no other pumps.. the water geo exchange you will need to likely have a variable speed pump so you can optimize your unit.