A heat pump is an excellent alternative to the standard HVAC setup of an air conditioner and a furnace. In operation, a heat pump resembles a central air conditioning system. Most of the components are the same: an outdoor cabinet with a compressor, fan, and refrigerant coil, and an indoor unit with an evaporator coil and air handler. The compressor places refrigerant under pressure so it circulates between the two sets of coils to carry out heat exchange.
A heat pump has several different components in it that allow it to work as a heating system in addition to a cooling system: