Forgot to mention that the MAG5 was driving a closed loop on my RO/DI tanks (just put together for my new system), and I ran the "Chiller" tube of an auxilary outlet with a valve I had turned WAY DOWN. Maybe I'll try again someday with more tubes (surface area).

Pete - I don't think the plastic tubing would exchange enough heat. The obvious heat exchanger would be a "Real" heat exchanger - Like a small radiator, but I wouldn't trust a stainless steel one, and I have never seen a reasoanble priced Titanium exchanger.

To make this idea work I think I would need 10-20 galss tubes enclosed in a duct box and the return air directed back to the A/C intake.