Heat Pump Education
The Basics of Heat Pump Technology
Unlike a gas furnace or wood burning stove, heat pumps don’t create heat; instead, they move heat from one place to another. This is possible because heat is naturally present in the earth and air, even when it is cold outside. Essentially, a heat pump functions as an air conditioner that can also work in reverse. In the summer, the equipment moves heat from inside to outside the home; and in the winter, heat is transferred from outside to inside the home.
Though heat pumps are rapidly gaining recognition across the United States as a smart solution for residential HVAC, basic heat pump technology has been around since the 1850s. You may not realize that refrigerators, freezers, and air conditioning units are heat pumps, which use a substance called refrigerant to move heat energy from one place to another. The technology is also used in high-efficiency electric water heaters.
Heat pumps use considerably less energy to heat and cool a home, all year long.
Since a heat pump system is powered by electricity, homeowners won’t spend time filling tanks, splitting and hauling wood, or dealing with the risk of fuel shortages or seasonal price fluctuations.
With heat pumps, homeowners have more control of their comfort. And, thanks to modern features, they can enjoy consistent heating and cooling with quiet equipment operation.
Heat pumps have an air filter that removes harmful particles from indoor air. Many models also provide dehumidification, reducing the likelihood of mold and mildew.
Since a basic heat pump is not powered by natural gas or propane, there is less risk of leaks and carbon monoxide poisoning.
Electric-powered heat pumps are designed to produce zero emissions on-site, and can utilize renewable energy sources like wind and solar—thereby reducing environmental impact.
Just about any home can benefit from a heat pump system, though it is imperative that a home is well insulated and air-tight prior to installation to maximize energy savings. Generally, the following are some of the best candidates:
- Heated by electric furnace or electric baseboards
- Heated by propane, wood, or fuel oil
- Looking to add air conditioning
- New construction or new room additions
- Manufactured homes
When considering a heat pump system, it is imperative for homeowners to purchase the most efficient model they can afford. While higher-efficiency heat pumps cost more upfront, the initial investment will pay off in lower operating costs and better comfort for years to come.
To assist with a heat pump purchase, homeowners can take advantage of rebates and tax credits for heat pumps that meet minimum energy efficiency ratings.
Understanding efficiency ratings
All heat pumps include efficiency ratings based on manufacturer testing to help consumers anticipate how well the heat pump will perform. These will be displayed as SEER, HSPF, EER, and/or COP. You may also see SEER2, HSPF2 and EER2, which are updated ratings meant to better reflect the efficiency of installed equipment. Developed by the Air-Conditioning, Heating, and Refrigeration Institute (AHRI)—and used by the U.S. Department of Energy (DOE)—these ratings are important to consider when gauging efficiency levels/operating costs and ensuring the heat pump selected qualifies for rebates and credits. Generally, for each of the below ratings, higher value = more efficient.
SEER (Seasonal Energy Efficiency Ratio) or SEER2: A measure of equipment energy efficiency over the cooling season. The rating of a unit’s cooling output (Btu) during a typical cooling-season divided by the total electric energy input (watt-hours) during the same period.
HSPF (Heating Season Performance Factor) or HSPF2: A measure of a heat pump’s energy efficiency over one heating season. The ratio of heat output (Btu) over the heating season to electricity used (watt-hours) during the same period.
EER (Energy Efficiency Ratio) or EER2: A measure of efficiency in the cooling mode. The ratio of total cooling capacity (Btu/h) to electrical energy input (Watts).
COP (Coefficient of Performance): This is the ratio of cooling or heating output to energy consumed at a specific temperature. This ratio converts both output and consumption to a common unit, making this different than HSPF or SEER, which use a ratio of BTUs to watt-hours.