GeoThermal Heating & Cooling
Ground Source Heat Pumps

The nuts and bolts of a Ground Source Heat Pump are very simple. It begins with the Heat Pump itself. A Ground Source Heat Pump can provide either hot and cold air, water, or a combination of both to your home heating and cooling distribution system. The heart of the Heat Pump is the refrigeration cycle using refrigerant, a compressor, heat exchanger and a reversing valve. Unlike a conventional central air conditioning system that has the compressor or condenser unit outside, a Ground Source Heat Pump unit is typically inside the home, not exposed to the outdoor elements. This is an added benefit when you are spending time outside. There is no noisy unit to bother you, no space is lost around the outside of your home, and landscaping becomes easier.

The second component of a Ground Source Heat Pump is the interface between the Heat Pump unit and the Ground Loop. This is typically called a Flow Center. The Flow Center is what pumps the water in the Ground Loop, through the Heat Pump heat exchanger and back to the ground loop and would also be located inside the building.

The third component is the Ground Loop. This is basically pipes in the ground that are exchanging heat between the water in the pipes and the ground. Depending on the season, we may be moving heat from the home to the ground or from the ground to the home, always heat moving to cold.

The Ground Loop has several categories and is comprised of Polyethylene Plastic Pipe that is joined by Heat Fusion and is designed to last well over Fifty (50) Years. The categories are open loop, closed loop, vertical and horizontal. An open loop is not a continuous loop of pipe; we are moving existing water from a source and then returning the water back to the source. The source can be from wells in the ground or a body of water. We at Radiant Comfort typically do not install open loop systems. Next is closed loop, which could be either horizontal or vertical. A closed loop is a continuous loop of pipe that circulates the same water from the pipes in the ground to the heat pump and back to the pipes in the ground. Typically there will be a non-toxic, environmentally friendly anti-freeze added to the water in the closed loop pipes.

A closed loop can be installed vertically or horizontally. In a horizontal installation, trenches are dug to a depth of 5-6 feet deep and pipes are placed in the trench, which is then backfilled. In a vertical installation holes are bored or drilled into the ground, pipes are inserted into the hole, allowing the pipe to go to the bottom and back to the top. The hole is then sealed with grout. These are sometimes referred to as wells, however they are not really wells because they are filled and sealed.

I realize that I have made all this sound simple, the basic Ground Source Heat Pump concept is simple. There will typically be several loops tied together to create a ground loop field. Some of the things that we at Radiant Comfort need to keep in mind are details such as: soil and rock conditions and what the ground conductivity is (or how well does this ground transfer heat) because not all ground is the same. Next would be how much Ground Loop Field do we need to provide for the heating and cooling needs for the building. If the Ground Loop Field is inadequate the system will not operate efficiently. Too much Ground Loop is not a problem for the system; it is a problem for cost of installation. Typically, the Ground Loop represents a significant portion of the installation costs so it is important to calculate the needs correctly.

Please contact us with any questions and we will be happy to help you.
We can discuss all options and answer all your questions while providing the on-site consultation and evaluation.