HOW DO HEAT PUMPS AND GEOTHERMAL SYSTEMS WORK?

There are two main components to a geothermal system: loop of buried piping and a heat pump.

The system works by extracting the warmth that is stored in the earth. This is done by installing a loop of piping a minimum of 7 feet underground where the temperature is approximately 50 degrees year round. An antifreeze solution is then pumped through the piping and brought inside your home where it circulates through a heat pump.

As the antifreeze solution, from the in-ground loop, passes through the heat pump heat is transferred to a refrigerant in a heat exchanger. The solution, now several degrees cooler, is circulated back to the ground where it is re-heated and then re-circulated to the heat pump.

The process of heating takes place in the heat pump. The refrigerant is pressurized increasing it to about 160 degrees. That superheated refrigerant then flows through another heat exchanger. If you have a forced air system, a blower fan forces air through the exchanger and into your home. If you have a hot water heating system the heat exchanger heats up the water which is then circulated through your radiators or in-floor heating lines.

THE IN-GROUND EARTH LOOP

There are several ways to install the in-ground piping:

One method is to install a slinky loop that lays the piping in the ground like a slinky. This method works well in large open areas.

Another is to create a vertical loop by installing the piping down a hole made by a well driller. This is usually more costly but works well on smaller properties

A horizontal loop is where the piping is installed using a horizontal drilling rig. Other options include a pond (or lake) loop and a “pump and dump” system. The last two systems are not as common and the "pump and dump" is losing favor as it requires significant amounts of well water.