A geothermal heating and cooling system consists of three main pieces of equipment:
- Underground loops of piping act as a heat exchanger. When the liquid antifreeze solution passes through the loops, it absorbs heat from the ground, which causes it to evaporate.
- An indoor heat pump unit includes the condenser coils. When the heated antifreeze vapor passes through the coils, it gives up its heat to the surrounding air and condenses back into a liquid.
- An air-handling system takes the heated air and moves it through ductwork to individual rooms.
During the summer, a reversing valve switches the indoor coil to act as the "evaporator" and the underground pipes to act as the condenser
Learn more about: The Anatomy of a Geothermal Heat Pump
In addition to the primary equipment, other components are integral, including:
Not all geo systems are alike - most provide summer air conditioning, but some models are designed only for winter heating.
Geothermal heat pumps also can be different in the way they're designed. Self-contained units combine the blower, compressor, heat exchanger and coil in a single cabinet.
All components of a geothermal system - except the underground loops - are placed inside a building, usually in the basement, garage or crawl space. Because they're indoors, the compressor and other vital parts are protected, with most having a life span of 20 years or more.