Many people may not have heard of heat pumps. They have been around for several decades and may be an option for regulating the temperature in your home. Think of a heat pump as an air conditioner with a few perks. To understand how a heat pump operates, it is necessary to know how modern air conditioning and cooling works.

Air conditioners and heat pumps are generally split systems. Split systems refer to cooling and heating systems that have an indoor component and an outdoor component. The indoor component of an air conditioner is the evaporator, often part of the furnace, while the outdoor components of an air conditioning system are the condenser and compressor. The outdoor system contains a gas called freon.

When the air conditioner is turned on, the compressor squeezes freon gas and pushes its molecules closer together. As more and more molecules get packed closer and closer together, the gas becomes hotter. Next, the hot gas flows into the other outdoor component called the condenser. There, the hot gas cools down and changes phases into a liquid.

Changing phases draws a large amount of heat out of the air. This cool air is then pumped back into the house and to the evaporator where it is pushed out by a fan and then down through the air vents. The cool freon then returns to the compressor where the process begins again. Heat pumps cool the air in homes and buildings the same way as air conditioners, however, they also have the benefit that they can act as heaters as well.

This allows home owners to have an all in one solution rather than separate heating and air conditioning systems. Heat pumps work by transferring air from one place to another, because air flows in one direction, from areas of hot to areas of cold. In the winter, the process of air conditioning is essentially reversed. The heat pump takes ambient heat from the air, or the ground depending on the model of heat pumps, and lets it flow over the coils that house freon.

The freon absorbs and stores the heat and a fan blows the warmed air out into the home. Heat pumps are also outfitted with electrical heaters that turn on on particularly cold days. They generally work best in regions where the temperature is moderate throughout the year. In areas where the temperature does not drop below 40 degrees, a heat pump may save more money than a furnace.

The industry measures heat pump efficiency based on cooling and heating. The Seasonal Energy Efficiency Ratio (SEER) is a rating of the cooling efficiency of the unit. A rating between 14 and 18 is ideal. The Heating Seasonal Performance Factor (HSPF) rates the heating efficiency of a heat pump. An ideal heat pump has an HSPF rating between 8 and 10. Heat pumps also have two-speed models in which air moves faster or slower as needed, thus saving energy.