Air conditioners work similar to a refrigerator. They use a chemical that can easily switch from a gas to liquid and back again. The chemical goes through a
compressor that, as it’s name suggests, squeezes the gas into a fluid. The fluid is then pushed into a condenser that cools the fluid. The fluid is then sent through an evaporator that causes the pressure to drop turning it back into a gas form. There is a fan connected to the evaporator that circulates the cooler air into the building.