hi all. I'm looking at buying a old waterfurnace geo unit. It being sold at a non profit resale store for $200 and includes no peripheral devices. they tell me it needs a $1000 dollar replacement part but they don't know what that part is , they also say that the fluid used for this unit is being phased out in 09. i know very little about these machines.   is this a good brand,  any ideas on what this $1000 part may be, can i use a different exchange fluid and will i need to purchase any external equipment like a water pump?  also i plan on using a old well for the ground heat source. it's about 4'  diameter and 10' deep, i don't know how much standing water is at the bottom. would something like this be sufficient?
i have allot of questions but right now i just need to know if any of this sounds like a good idea to any of ya  out there who might have some experience with this sort of thing.  thanks all!

This is a pretty scary deal. The $1000 part could be the fan, the compressor, the ECM board, the air coil, the water coil and a few more that I can't think of right now. You can't change type of refridgerant . What is the capacity of this unit? (how many tons ?) You need to know that before you can tell if you have enough water. 4' x 10' is pretty small, I don't see you getting enough capacity out of that. You would need an external water pump to get it to work.

I would stay far away from this scary deal.

Tom, something to keep in mind on the motors. If you have a 240 volt motor that draws 10 amps, then you would be able to use a 16 AWG wire. If you change that to a 24 volt motor it would then draw 100 amps, requiring you to use a #3 AWG wire. Thats alot of extra copper and takes a lot of space. Greg

Nothing is impossible for the truly determined who has unlimited resources!!!

From a practical standpoint, the odds are somewhere between zero and none!!! Main reason being virtually all HVAC compressors of the size you're looking at here are hermetically sealed inside the can with the motor.

Johnny Carson's "The Great Karnac's" questions weren't the only things in the world hermetically sealed!!!