how works a heating pump?
A heat pump works just like a refrigerator. It moves heat from one sure to another, using the compression and expansion of gases to do the work. The heat pump operation is different from that of a refrigerator, in that it can move heat in two directions. Compressing a gas to a liquid makes it hot. Vaporizing a liquid cools it. To heat the house, the heat pump compresses gas, and a heat exchanger cools the resulting liquid. The liquid is pumped to the outside of the house, where it is expanded. Outside air heats the expanded gas, which is then returned to the house. To cool the house, the process is reversed.
