Geothermal systems use the earth as a heat source and heat sink. In order to transfer heat to or from the house heat exchangers (ground loops) are installed in the ground. These consist of high density polyethylene plastic pipes. The loops are then connected to the heat pump and fluid circulated between them transferring the heat between the heat pump and the earth.
Horizontal Ground Loop System
This type of design is cost effective on smaller projects or where there is sufficient space for the loop. Trenches, three to six feet deep, are created and a series of parallel plastic pipes are laid inside them. These loops are mainfolded and connected to the heat pump. The fluid is then circulated absorbing or rejecting heat to the earth depending on the mode of operation. A typical horizontal loop will be 400 to 600 feet long for each ton of heating and cooling but will vary according to the soil type and the layout of the piping.
