How does an reverse cycle air conditioner work?

First, one should understand how a regular air conditioner works. Basically (without complicated thermodynamics), electrical energy is used to pump heat from inside to the outside, because the inside air isn't just randomly going to cool off. That is, it takes energy (work) to make something colder than its surroundings. ( <a href="http://home.howstuffworks.com/ac1.htm" target="_blank" rel="nofollow">http://home.howstuffworks.com/ac1.htm</a> if you want more) Maybe you've noticed that the outside of an air conditioner or maybe the back of a refrigerator gets quite hot in operation. The reverse cycle air conditioner exploits this as a heating device for the inside, cooling off the outside air. In detail, the outside air isn't going to just cool off so the inside air can get warmer, so electricity is used to move some of the heat energy from the outside to the inside. Thus, the heat coming from this this inside will be the electrical energy used plus whatever is energy is taken from ...  more