We installed our Waterfurnace geothermal system in 2009 and have yet to have one service call. Ever. Our unit is on the beach and my neighbors have all replaced their conventional HVAC systems at least 2 times now in the last 8 years due to salt corrosion. Our unit is still humming along nicely.
I thought I would add some positive perspective on our experience since it seems only "pissed consumers" go on this site.
After reading a majority of the reviews it appears many of the issues lie with the customers choice of installing contractor. The guy who installed ours was a very experienced GeoPro dealer who had the portfolio, references, licensing & knowhow to make us feel like he was the right choice. He also was not the cheapest as we are aware that cheaper is usually a "pay me now or pay me later" scenario.
My advice to any purchaser of Geothermal is to do your homework and certainly do not try to "pinch" your installer to get a Rolls Royce for the price of a Pinto. It can not happen and honestly some dealers should learn to walk away from those deals/customers rather than attempting to take on a project they can not properly do or feel comfortable installing.
Reason of review: Good quality.
Waterfurnace Pros: Product is holding up better than my neighbors, Energy savings.