I have two separate GSHP systems, installed in March of 2011. One system, a package unit, is installed behind the knee-wall of my office above the garage. The final connections for the loops are rubber hose enclosed in a soffit along the garage ceiling. It's been seven years since we installed the system and it has required no maintenance until now. The service tech checked the codes and then the water pressure and, as I had guessed, it needed water. I was worried that that meant I had a loop leak (in vertical bores that are back-filled with grout). The tech said not to worry, there is no leak. The issue is that rubber hose will expand when it warms up but not contract when it cools down thus allowing the water pressure to be reduced. Since the garage area is not conditioned and summer temperatures in Raleigh are regularly in the nineties my rubber hose had expanded. A little water in the pipes and everything is fine! The second unit is a package unit installed in the crawl space under my house. When it failed to start I assume that it needed a little water, like the other unit did. Wrong! The issue was that mold had built up in the condensate drain trap and needed to be cleared. A wire brush and a little bleach and everything was fine! I will make sure to clear and test my condensate drains on a yearly basis in the future.