This type of loop system is generally the most cost-effective option for residential installations, especially for new construction where sufficient land is available. This type of system is installed within trenches that are between four to seven feet deep. A series of plastic pipes are laid inside of the trenches and connected to the heat pump. A typical horizontal loop will be 400 to 600 feet long for each ton of heating and cooling.

Vertical loop systems are commonly used for commercial buildings with limited space. It starts by drilling vertical holes in the ground that are anywhere from 150 to 400 feet deep. Then, a single loop of pipe with a U-tube at the bottom is installed. The hole is then sealed with grout to ensure adequate contact with the soil. Lastly, the vertical ground loops are connected to a horizontal underground header pipe that is responsible for carrying fluid to the unit.

If a building is located near a body of water, a pond/lake system may be the most economical choice. A supply line pump is run underground to the body of water and is coiled into circles at least eight feet underground to prevent freezing. In order for this type of system to work, it must be placed in a body of water that meets its minimum volume, depth, and quality criteria. It’s important to note that pond/lake loops have no adverse impact on the aquatic environment.

This type of system is only possible if there is sufficient groundwater available via a well, lake, or river. The water source must be of good quality and comply with local groundwater discharge codes. Since the system is open, a water pump is placed directly into the geothermal unit and then discharged into a return well or a body of water. The system does not affect the water’s quality.