Ground loop – A closed ground loop system consists of a series of high density polyethylene pipes buried in your yard. A heat transfer fluid, comprised of antifreeze and water, is inside the ground loop pipes. This heat transfer fluid removes heat from (heating mode) or delivers heat to (cooling mode) the earth surrounding the ground loop. The ground loop pipes carry the heated fluid to the heat pump furnace unit in the home. See ground loop configurations.
Heat pump furnace unit – The heat pump's system upgrades the heat, which is then circulated throughout the home by way of the distribution system. The heat pump furnace unit provides both heating and cooling.
Distribution system – In a forced air system, a fan in the heat pump furnace unit blows air over a fan coil and the heated or cooled air is distributed through the home's ductwork. In a hydronic system, hot water is circulated through radiators or a system of in-floor pipes to provide heat.
Desuperheater – Geothermal heat pumps may include a device known as a desuperheater to help with domestic water heating. In summer, the desuperheater recovers some of the heat that would otherwise be sent to the ground loop to help produce hot water. In winter, some of the capacity of the heat pump may be diverted from space heating for the same purpose. Desuperheaters save approximately 25 per cent on domestic water heating costs.
Supplemental/auxiliary electric heater – The majority of geothermal heat pump systems are designed with an auxiliary electric resistance heat built into the system. Typically this auxiliary electric heat is installed to allow your contractor to more optimally size the geothermal heat pump system for the home's base heating load, and allow the electric heat to assist the system during the few coldest days of the year. In addition, this provides an emergency backup heat source if there are any operational issues with the geothermal heat pump system.