Gas and Propane Refrigerators
If you own an RV or use a refrigerator where electricity is not
available, chances are you have a gas- or propane-powered
refrigerator. These refrigerators are interesting because they have
no moving parts and use
propane as their primary source of energy. Also, they use heat,
in the form of burning propane, to produce the cold inside the
A gas refrigerator uses ammonia as the coolant, and it uses
water, ammonia and hydrogen gas to create a continuous cycle for the
ammonia. The refrigerator has five main parts:
The cycle works like this:
- Generator - generates ammonia gas
- Separator - separates ammonia gas from water
- Condenser - where hot ammonia gas is cooled and
condensed to create liquid ammonia
- Evaporator - where liquid ammonia evaporates to create
cold temperatures inside the refrigerator
- Absorber - absorbs the ammonia gas in water
offers an extremely detailed description of the process.
- Heat is applied to the generator. The heat comes from burning
something like gas, propane or kerosene.
- In the generator is a solution of ammonia and water. The heat
raises the temperature of the solution to the boiling point of the
- The boiling solution flows to the separator. In the separator,
the water separates from the ammonia gas.
- The ammonia gas flows upward to the condenser. The condenser
is composed of metal coils and fins that allow the ammonia gas to
dissipate its heat and condense into a liquid.
- The liquid ammonia makes its way to the evaporator, where it
mixes with hydrogen gas and evaporates, producing cold
temperatures inside the refrigerator.
- The ammonia and hydrogen gases flow to the absorber. Here, the
water that has collected in the separator is mixed with the
ammonia and hydrogen gases.
- The ammonia forms a solution with the water and releases the
hydrogen gas, which flows back to the evaporator. The
ammonia-and-water solution flows toward the generator to repeat
Next, we'll look at electric coolers.