Inside a Geothermal Heat Pump

Recently, many inquisitive Salem residents have asked Mill Creek Heating about geothermal. Sure, geothermal heat pumps use the earth to condition your home... but how do they do it?

This marvelous system works thanks to one simple principle: Given the opportunity, heat seeks out and moves towards cooler temperatures. That's why an ice cube melts and it's how a geothermal heat pump is able to deliver heat. Here's how geothermal works :

In the absence of a combustible material, geothermal systems obtain heat differently. It simply collects and moves it using the principle stated above. In order to carry heat energy from one major component of the system to another, a special liquid called refrigerant is used. The refrigerant is moved throughout the system by a powerful centrifugal pump called a compressor.

During the summer, a blower circulates warm indoor air through your home's duct system. The air is eventually forced across a series of metal pipes and thin fins called an air coil. The air coil houses cold refrigerant and naturally absorbs the undesirable heat from your air. The refrigerant carries that heat into the compressor where it's put under a large amount of pressure. When refrigerant is put under pressure, its molecules are concentrated and collide more often - making it very hot.

Next, the hot refrigerant is pumped through a copper tube-within-a-tube called the coaxial coil. The inner tube contains water circulating from underground pipes (called a loop), while the outer tube contains refrigerant. The refrigerant passes its heat through the wall of the coil and warms the loop water. A loop pump circulates the warmed water back underground where the heat that began in your home is deposited into the earth. At the same time, the refrigerant in the coaxial coil is pumped through an area of low pressure called an expansion valve. The decreased pressure allows the refrigerant to expand rapidly. When refrigerant expands, its molecules get farther apart and collide less often - making it very cold. The cold refrigerant is now ready to be circulated back to the air coil, where the process can begin again.

To heat your home, the system literally reverses the entire process using a reversing valve. Refrigerant flows in the opposite direction and order of components.

Mill Creek Heating hopes this information has been helpful in your decision to install an energy-saving geothermal system. We install one of the most efficient geothermal heat pumps on the market. We serve all of Salem and the surrounding areas. Contact us today.