What Makes a Heat Pump Work?

March 01, 2013

Throughout the Mobile AL area, home and business owners rely on heat pumps to keep their buildings cool in the summer and warm in the winter. These compact, efficient devices pull double duty by pumping heat into and out of the home as desired, maintaining a comfortable temperature all year long. Understanding how a heat pump works is as simple as understanding a few basic properties of matter and the ways in which heat pumps use those properties to transfer heat.

How a Heat Pump Works

Learning how a heat pump works begins with a basic grasp of phases of matter. When any substance evaporates, going from a liquid to a gas, it absorbs energy in the form of heat to make the jump to a more energized state. Conversely, when a gas condenses and becomes a liquid, it releases that stored energy in the form of heat. These phase changes are thus a very efficient way to move heat from one location to another.

Air conditioners transfer heat by forcing refrigerant chemicals to go through these phase changes in a constant cycle. At the evaporator coil, refrigerant absorbs heat and evaporates; the machine then transfers this gaseous refrigirant to the condenser coil, where it is put under enough pressure to become liquid again. This phase change releases heat, and the machine transfers the liquid refrigirant back to the evaporator coil to repeat the cycle. Heat pumps use the same cycle during cooling, but in heating mode they reverse it and transfer heat from the outside in. Essentially, the heat pump acts as an air conditioner for the outside air and pumps the collected heat into the house.

Although the heat pump’s two cycles use essentially the same process to transfer heat into and out of the home, they are not equally efficient. Every heat pump’s heating cycle is given a heating seasonal performance factor (HSPF), and the cooling cycle is rated with a seasonal energy efficiency ratio (SEER). The higher the HSPF, the more efficiently the machine uses power during the heating cycle; likewise, a higher SEER means the machine uses power more efficiently in the cooling cycle.

Benefits of a Heat Pump

Because heat pumps effectively serve as two machines in one, they are great options for homeowners who want to save space without sacrificing heating and cooling power. They also tend to be quite energy efficient, especially in areas where the air never gets extremely cold. As long as there is some heat in the outdoor air, the heat pump doesn’t have to work terribly hard to transfer energy into the home.

Thanks to Alabama’s hot summers and mild winters, heat pumps are some of the most efficient heating and cooling appliances around. At Keith Air Conditioning, we strive to provide our friends and neighbors with the best in heat pump installation, service and maintenance. To learn more about these powerful machines or schedule a consultation, give us a call today.