A practical question about that cycle: i've just bought a new fridge and looked at the refrigeration cycle for the first time in 5 or so years. Now, i feel that the condenser at the back is quite warm (as it should be) and is being cooled by my room. All good and well. But how does the evaporator work? I mean, i understand that the superheated gas turns into a liquid, but how does that liquid become as much as 30 or so degrees Celcius so that it can be cooled by the environment later, despite (after a while) being heated by air of only 7 or so degrees? Edit: Also, can anyone confirm if the efficiency is 1 - Tc/Th?