How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Robert Your Own Question
Robert, RV Mechanic
Category: RV
Satisfied Customers: 13375
Experience:  18 yrs. RV experience including Cummins North West, Country Coach, Monaco Coach - vendor certified.
Type Your RV Question Here...
Robert is online now
A new question is answered every 9 seconds

How do the RV refrigerators work? Why do they need gas to operate?

This answer was rated:

How do the RV refrigerators work? Why do they need gas to operate?

Hi There...

Trying to keep this simple, Gas RV refrigerators are entirely different from their electric cousins. Where electric refrigerators use safe, non-flammable Freon for their refrigerant, gas (propane) RV refrigerators use compressed hydrogen gas and an ammonia-water solution. Electric refrigerators use compressors, electric motors, and cooling fans; gas refrigerators have no moving parts. IF you are still interested on how the process works you can click HERE and it will explain what each component does in the cycle. It also explains why a RV fridge needs to be level, very good article.

IF you are having issues with your unit please let me know if you have any questions on that..... Robert

Customer: replied 5 years ago.
I would like to know more than the simple answer. If using compressed hydrogen gas and ammonia, what is the propane for?


The LP is used to heat the vessel that contains the ammonia solution. This can be do with LP or the AC heating element for the fridge.

It has five main parts.

  • Generator - creates ammonia gas
  • Separator - separates the ammonia gas from water
  • Condenser - where hot ammonia gas is cooled and condensed to create liquid ammonia
  • Evaporator - where liquid ammonia converts to a gas to create cold temperatures inside the refrigerator
  • Absorber - absorbs the ammonia gas in water
  1. Heat is applied to the ammonia and water solution in the generator. (The heat comes from burning gas, propane) As the mixture reaches the boiling point of ammonia, it flows into the separator.
  2. Ammonia gas flows upward into the condenser, dissipates heat and converts back to a liquid.
  3. The liquid ammonia makes its way to the evaporator where it mixes with hydrogen gas and evaporates, producing cold temperatures inside the refrigerator's cold box.
  4. The ammonia and hydrogen gases flow to the absorber where the water collected in the separator in step No. 2 mixes with the ammonia and hydrogen gases.
  5. The ammonia forms a solution with the water and releases the hydrogen gas, which flows back to the evaporator.
  6. The ammonia-and-water solution flows toward the generator to repeat the cycle.
Robert and 3 other RV Specialists are ready to help you