I have a 20 gallon per minute, 68 degree F flowing artesian well 200 feet from my house. Can I use this free water source to cool my Heat pump?

 

If you mean by modifying a standard air heat pump somehow....I doubt its a good idea. If you were to replace it with some type of ground water heat pump...maybe....but what happens if the artesian well dries up?

 

Thanks, these are questions I will certainly have to consider.

 

The minerals in the water will kill your coil

 

I have done what you proposed and if done correctly, will enhance the efficiency of your condensing unit. You can attach a ground loop of copper right off the compressor running underground or in a PVC conduit for protection. Put at least a 10' loop of copper into the water before it returns to go back into the liquid line to the air handler. Use insulation on the line going back to the air handler to reduce picking up heat on the way back. Disconnect the out door fan as you won't need it. You will need to have a pro do the hookup for you and the system charge will need to be adjusted to compensate for the additional copper run. Bear in mind, there is danger associated with this; a punctured copper line in the water will allow water into your system and most likely ruin it all; routing copper underground "should not" be a problem unless your soil is highly acidic and might attack the copper; your a/c tech will have to measure the return line temp to be sure you have enough copper in the water; if the water source dries up you will have high head pressures on the compressor and problems.
There is all kinds of sophisticated control that can be attached to this to prevent problems. For instance a reversing valve can be put into the freon circuit controlled by a temp sensor on the return line in the event that the water source is not taking out enough heat. It could then automatically switch the unit back to using the air exchange condenser and turn the outdoor fan on. High and low pressure shut down sensors can terminate running if pressures are not correct. You are getting into custom adaptations that if correctly done by a very knowledgeable tech can work quite well. It will cost a little to get it done but you can see a pretty good saving in energy particularly if this is a heat pump and your winters require much heat. The 68 degree water would be a wonderful heat source. Alternately, you could hook a water to freon heat exchanger into the freon circuit and with a small electric water pump in a closed water loop to the artesian well get much the same result. Either way, this is not a DIY project unless you have electrical and A/c backround and equipment. DO NOT attempt to just pump the water over the condenser coils, yes it will work for a while but you are slowly building a bomb.