A Geo-exchange system utilizes the near-constant (less than 35 feet) or constant (more than 30 feet) temperature of the ground to heat or cool. It is a type of Heating, Ventilating, and Air-conditioning (HVAC) system (some systems don't incorporate ventilation, however). Geo-exchange systems are usually comprised of a target structure (the building to be heated/cooled), a heat pump, and a sink. The heat pump consists of working fluid, a loop field, and a heat exchanger. The working fluid flows… (More on Geo-exchange)