
Air Source Heat Pumps
If you heat your home with a central, ducted system, changing over to a heat pump could save you money, and add the comfort of air conditioning in the summer months. The key to a heat pump’s efficiency comes from the fact that it does not create heat but instead, moves heat from one place to another.
- In cooling mode, an air-source heat pump evaporates a refrigerant in the indoor coil; as the liquid evaporates it pulls heat from the air inside the house. After the gas is compressed, it passes into the outdoor coil and condenses, releasing heat to the outside air.
- In heating mode, an air-source heat pump evaporates a refrigerant in the outdoor coil; as the liquid evaporates it pulls heat from the outside air. After the gas is compressed, it passes into the indoor coil and condenses, releasing heat to the inside of the house.

Air source heat pumps have been around for decades in moderate to warm climates, however, years of advancements mean that cold-climate models are available to deal with Montana winters. Even the best heat pump will require some form of back-up when temperatures fall below freezing. One solution is to install electric resistance heat strips (which resemble the coils in your toaster) in the heat pump unit itself. Alternatively, a heat pump may be added to an existing electric, gas or propane furnace, making the existing system a back-up for the heat pump.
If you think a heat pump might be right for your home, call MEC to find out how you can qualify to receive rebate for installing a new heat pump in your home. Keep in mind, a Performance Tested Comfort Systems (PTCS) certified technician will have to install your heat pump. For a list of PTCS certified installers, click the link to search the PTCS registry.