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Heat pumps are a popular choice for central air in the South.
Theyboth heatand cooldespite the somewhat misleading nameand can help save money on utilities.
How Heat Pumps Work
Unlike a traditional furnace, heat pumps don’t generate any heat.
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A heat pump is a single system that can both heat and cool by absorbing and transferring heat.
In winter, heat pumps extract heat from the outdoors (or underground) and pump it inside.
Air-source heat pumps are much more common because of the ease and cost of installation.
Geothermal heat pumps work by pushing heat underground or pulling it from underground, depending on the season.
They come in a range of sizes and levels of energy-efficiency.
Most air-source heat pumps do best in a mild climate with winter temperatures that rarely drop below freezing.
Fluid-filled pipes and an indoor air handler work to transfer heat from or to underground.
Geothermal heat pumps are expensive to install because of the extensive piping required.
The heat pump compressor moves refrigerant through the coils to capture or release heat.
The fan blows air across the coils to warm up air or cool it, depending on the season.
An expansion valve controls the pressure and temperature of refrigerant in the coils.
Some air-source heat pumps have an emergency heating system that kicks in whentemperatures dropbelow freezing.
These systems use electricity to produce heat and can become expensive to run in cold climates.
Refrigerant in the coils captures the heat, cooling the air to then send through your ductwork.
The system sends the warm refrigerant indoors, where it evaporates heat when air blows across the cools.
The air then travels through ducts to warm your home.
The refrigerant in the indoor unit cools and condenses, and is sent back outdoors.
However, heat pumps are more eco-friendly than gas furnaces because of reduced emissions.
Some companies sell cold-climate systems that can run at much colder temperatures.
Change air filtersregularly, just like you would for a traditional furnace or air conditioner.
Baugh, T.What Is a Heat Pump And How Does A Heat Pump Work?Carrier.
U.S. Department of Energy.Guide to Geothermal Heat Pumps.
U.S. Department of Energy.Heat Pump Systems.
