A Geothermal Heat Pump is a machine that can be used to heat and cool your home. It works by using the heat underground to warm and cool your home. A pipe is buried underground, liquid flows through the pipe, and the heat from the ground warms up the liquid. The warmed liquid goes into a heat pump in your home, which then uses the heat to heat the air in your home. In the summer the process is reversed. The heat from your home goes into the ground and the cooler liquid from the ground goes back into the heat pump to cool the air in your home.