An air-to-air heat pump has many of the same components as an air conditioning system. The majordifference is?
Actually, they are the same, and often the same unit does both functions, (winter heating and summer cooling). The only difference is that it works in reverse, that is in winter mode it absorbs heat from the outside air and radiates it inside, and by switching which of the two heat exchangers is getting the pressure, (summer mode), it absorbs heat from the inside and radiates it outdoors. This change-over is done using electrically operated valves that effectively reverse the direction of the compressor to reverse the action.
