Ground Source Closed-Loop Heat Pumps

Ground source closed-loop heat pumps use the same concept as the ground source units - the temperature of the earth near the surface is typically around 55°F. The difference is no water is taken from the ground or disposed of. The water is circulated to the individual heat pumps and the returned to a ground loop to be cooled or warmed.

When more units are heating than cooling the circulating water temperature drops and is warmed back up by the earth. Conversely, when more units are cooling than heating, the circulating water is cooled down by the earth.

The heat is transferred by either horizontal pipe coils buried in the ground or down-hole heat exchangers. The down-hole system is used when surface area is limited since horizontal or even spiral coils can take up a lot of room and run up excavation costs.