Recent Review: Our 17 year old ClimateMaster geothermal unit quit on one of coldest days of winter. One of GeoSource's techs arrived on time as promised, identified problem and most of all, had parts in his van enabling him to get the unit working. Have used GeoSource at least twice before and have been very satisfied. Should have recommended them long ago. It's hard to find competent geothermal technicians in Connecticut, let alone Fairfield County. This company specializes in geothermal alone. We've found other HVAC companies who claim to service geothermal, have to send a follow-up technician who knows geothermal after the first tech is unable to figure out what's wrong. If your system is geothermal, get a specialist!