Ground Loops in Knoxville, Tennessee, Geothermal Applications

You’ve finally gotten, or are considering getting, a a new heating and cooling system. Maybe you’re weighing the advantages of a new Geothermal HVAC. Whatever the circumstances, you undoubtedly want to know a little bit more about how one works.

Geothermal HVACs variously cool and heat your home by extracting ground temperature. This is possible because of an underground system called a geothermal ground loop.

Ground loops are pretty much just a system of pipes buried in the ground. A few basic kinds of these systems are used for heating and cooling most residential and commercial buildings.

Antifreeze fluid flows through the pipes to transfer heat quickly and efficiently to a heat pump in your home.

Typically used are four different types of ground loops: Open Loop, Pond Loop, Horizontal Loop and Vertical Loop. These are divvied up into two categories categories: either they’re open loop systems or closed loop systems. The appropriate system for your house is determined by the structure and the environment surrounding it. Residential systems primarily use vertical or horizontal loops.

Below are more specifics on each type of ground loop.

Closed systems, which include vertical, horizontal, and pond loops, continuously circulate water through them.

Vertical ground loops are used typically in residences because, unlike horizontal loops, they don’t have to have a lot of space. They’re installed by drilling tight-diameter holes in the ground that extend 100-400 feet deep. Then pipes are placed into the holes and connected below ground to form the vertical loop. Next, additional pipes are attached that carry fluid to the indoor system to transfer the necessary temperature from the ground.

A horizontal loop system has to have significantly more space but usually is less pricey because it uses only 2 straight pipes placed 6 inches down in the ground in an area of ¼ to ¾ acre.

In order to have a pond loop system, it should go without saying that you must be in close proximity to a pond, lake, pond, or well. Coils are installed vertically and fastened to the bottom of the water source. Water is then transferred through more pipes beneath the earth to a pump, where the heat is extracted and cool water is returned to the pond. That said, in order for this system to work, the water can not be acidic or else pipes will decay and filters will need to be replaced often.

The essential difference between open and closed looped systems is the open loop’s need for an adequate source of groundwater, like a well or pond. From there, it directly pumps water into the heat pump unit for use in heating and cooling your house or other structure.

Most often, used water is taken care off in either of these ways: through surface drainage or water re-injection. In returning the water back to the earth, it’s worth noting that there’s no pollution. The only difference in water that’s processed through a geothermal heat pump is a negligible change in temperature.

Before you install an open loop system, it is vital to know whether a well or pond holds enough water to power your geothermal heat pump, and that it won’t drain a neighbor’s well source. Make certain you check with your local contractor on whether there’s enough water in the vicinity to justify installing an open loop geothermal heating system.