The key to the heat pump’s performance is in its utilization of the heat transfer process. In the summer, the heat pump actually works just like a central air conditioning system. Refrigerant is evaporated in the indoor (evaporator) coil of the system. This draws heat out of the air. Then, the refrigerant is condensed in the outdoor unit. The condenser coils help to vent the heat out into the air outside.
What sets the heat pump apart is the fact that it can reverse its operation. This is thanks to a component called the reversing valve. In the winter, the system reverses not only the flow of refrigerant, but also the operation of its coils. Now, the outdoor coil acts as the evaporator coil, with the evaporation of refrigerant allowing it to absorb heat from the air outside. The refrigerant is condensed indoors, and this heat is used to warm your home. And while it may not produce the same amount of heat as a furnace, it is far more dynamic and often more efficient!