I have a climatemaster 6 ton unit with a 3600ft horizontal closed system pressureless loop. Its about 10 years old. It worked great for years but the last couple years it seems that it has become less efficient. If the outside temp gets below freezing it cant keep up. If the the outside temp gets too high it cant keep up. When it was working properly no matter what the outside temp was the inside temp was always what it was set to on the thermostate. Also, I noticed a black film in the loop water. Is it possible that I have some kind of buildup inside the loop or the coils inside the unit that is causing the unit to be less efficient. There is also ice buildup in side the unit around the coil. The unit is running non stop when it gets cold and can not maintain the set temp in the house. My installer has long gone out of business so I'm having a hard time finding someone who is familiar with geothermal, so any help there would be appreciated. I live in the Atlanta area north east of the city. Any suggestions or references would be greatly appreciated.
I see two issues First what is growing in the geo loop system. I have learned here of late that goo can grow in a glycoal mix that is lower than what I use here in Cleveland. Depending on where the unit is frosting you could have a refrigerant leak. I think it is time to find a good refrigeration/geo heat pump tech and have him come take a look. Start with "Find-a-Pro" at this site. Be sure to tell him what is in the loop system so that he can bring the correct test stuff.
Loop Water I know that I have only water in the loop. One of the techs that worked on it in the past said that did not need any additives in the water. Could that be what's causing such poor performance? Thanks for the help.
My first impression guess would be you are low on refrigerant. If you are icing up in an area where antifreeze isn't used, then I can't think of much else. As Mark said try to find a pro here. Another resource might be the IGSHPA accredited installer list for your area. Good Luck, Joe
