Heat pumps

Air-to-air heat pumps

Water-to-air heat pumps (water serves as heat source)

100°

FIGURE 14.8a A simple through the wall air conditioner unit essentially consists of a compressive refrigeration machine.

REVERSING VALVE

OUTDOORS 40° F

«t—

FIGURE 14.8b

In a "heat pump" the reversing valve allows the refrigerant to flow in either direction. In the winter condition shown, the outdoor coil becomes the evaporator and the indoor coil the condenser.

Heat source/sink: O

Air source — low cost, and it is least efficient. Water (ground) source — high cost, and it is more efficient than air.

Posted in Fundamentals of Heating. Ventilating, and Air-Conditioning