- In a propane refrigerator (also known as an absorption refrigerator), a burner warms a mixture of water and ammonia in the generator. Ammonia boils at a lower temperature than water, so the ammonia bubbles away into the condenser coil while the water stays in place. When the ammonia reaches the condenser, it cools and turns back into liquid ammonia.
- The ammonia next flows into the evaporator coil, where the actual refrigeration happens. In the evaporator, the ammonia mixes with a low-pressure hydrogen gas. The low pressure in the system causes the ammonia to rapidly turn into a gas. When it turns into a gas, the ammonia cools. A fan in the refrigerator blows air over the coil. The coil cools the air, which then circulates through the refrigerator.
- The absorber trickles water into the mixture of hydrogen and ammonia. Hydrogen does not mix with water, but ammonia dissolves in it easily. As water trickles through the mixture, it leaches out the ammonia and takes it back to the generator.











