Heat Pumps Explained: What Are They, and How Do They Work?

March 14, 2022
Heat Pump in Orchard Park, NY

In the past, homes had separate equipment for heating and cooling — usually a furnace and an air conditioner. However, heat pumps can offer a convenient solution to your cooling and heating needs all in one. The first true heat pump was invented in the 1940s, but it wasn’t until much more recently that they really began to catch on. As a result, most people know very little, if anything, about what heat pumps are and how they work. With this in mind, here is a quick overview of heat pumps to help clue you in.

The Parts of a Heat Pump

A heat pump consists of two primary parts. On the outside of the building is a condenser/compressor unit, and this is connected to an air handler inside the building. With a standalone heat pump, the air handler is connected to your home’s ductwork and existing HVAC system. However, there are also ductless heat pump systems that use their own air handler. Sometimes called ductless mini-splits, these units function exactly the same way as a standalone heat pump. The only difference is where the air handler is located.

How Heat Pumps Provide Cooling

Heat pumps can be used to provide both heating and cooling. When turned to cooling mode, the heat pump works exactly the same way as a traditional air conditioner. Both systems work based on the principle of heat transfer. Under the laws of thermodynamics, heat automatically flows from a hot area to a cooler area. Heat pumps use this principle to absorb heat from inside the home and transfer it outside.

Basically, the condenser unit is designed to produce extremely cold refrigerant. This cooled refrigerant is then transferred to a series of coils inside the air handler. As the warm air inside the home is drawn into the air handler and passes over the coils, the refrigerant absorbs all of the heat from the air. This cools the air, and this cold air is then circulated back through the house. During this process, the refrigerant heats up. The condenser works to continuously send cold refrigerant into the system. It also constantly draws warm refrigerant back out and releases the heat into the air.

How Heat Pumps Produce Heat

The difference between a heat pump and a traditional air conditioner is that heat pumps can work both ways. When providing heating, the same heat transfer process is reversed. Instead of drawing heat out of the house, the condenser draws heat from the air outside.

To provide heating, the compressor uses extremely cold refrigerant to draw heat from the air outside the building in order to warm up the refrigerant. The unit also uses a compressor to compress the refrigerant, which drastically increases its heat in a matter of seconds. This heated refrigerant is then transferred to the air handler. As air is drawn into the handler, the heated refrigerant coils transfer the heat to the air. The system works in a loop with cold air constantly being drawn in through the return air grates and hot air being pushed out through the vents.

Because of the principle of heat transfer, this process can continue to happen as long as the refrigerant inside the condenser is colder than the air outside. In most cases, a heat pump can continue to produce at least some heat at temperatures as low as -4 degrees Fahrenheit. Nonetheless, the efficiency of a heat pump is drastically reduced as the temperature drops, which means you may still need a secondary heat source on extremely cold days.

Heat pumps are far more energy efficient than a conventional furnace, and they only require electricity to work. If the heat pump is working properly and the conditions outside aren’t too cold, the unit could potentially work at up to 300% efficiency. This essentially means that it is producing three times as much heat energy as the electricity it is using. On the other hand, even the best high-efficiency furnace can only achieve around 95% efficiency under ideal conditions. Still, heat pumps are at their most effective when the temperature is above freezing.

Heat Pumps and Other HVAC Solutions

At Vastola Heating & Cooling, we carry a range of highly efficient heat pumps from top brands like Carrier and Lennox. Our expert technicians can also service and repair all models of heat pumps and other HVAC equipment. Some of the other areas we specialize in include indoor air quality, duct sealing, boilers, water heaters, snowmelt systems, and generators. Vastola Heating & Cooling is located in Orchard Park, NY, and we serve customers throughout Erie County. If you have any questions or want to schedule a service appointment, give us a call or fill out our contact form.