How a Geothermal Closed Loop System Keeps Your Home Comfortable

A geothermal closed loop system is the most common and usually the most cost-effective way to heat and cool with geothermal energy. Like all geothermal heat pumps, these use the ground as a heat sink to extract heat (in heating mode) or deposit heat (in cooling mode).

An open loop system circulates water from a pond or other source through the ground loop’s pipes, then discharges that water back into the ground. A closed loop geothermal system, however, uses a heat transfer fluid that’s sealed into the loop. A geothermal closed loop system consists of three main parts:

• Ground heat exchanger — Known as the loop, this is a set of pipes buried underground. The pipes contain a water/antifreeze mixture that circulates through them. Unlike with an air-source (conventional) heat pump, there is no outdoor unit. The loop replaces the outdoor unit.
• Heat pump — The indoor heat pump unit houses a heat exchanger, compressor, condenser and other standard heat pump components. The antifreeze mixture in the loop flows past the heat exchanger to exchange heat with it.
• Delivery system — This is usually either ductwork or a radiant floor system. When the system’s in cooling mode, the antifreeze mixture circulates through your indoor unit and absorbs heat from your home. The mixture then flows out to the ground loop, where it circulates and releases heat into the earth. Once cool, the antifreeze mixture flows back to your home to absorb more heat. To heat your home, the antifreeze mixture circulates through the loop to absorb heat from the earth. It then flows to the indoor unit, which extracts the heat. A geothermal closed loop system is more reliable and requires less maintenance than an open loop system. With a closed loop system, there’s no risk of running out of your clean water supply or picking up pollutants from the ground.

To learn more about how a geothermal system can keep your home comfortable, contact us at Sobieski Services. Our goal is to help educate our customers in Delaware, Pennsylvania, Maryland and New Jersey about energy and home comfort issues (specific to HVAC & plumbing systems).

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