How Does a RV Refrigerator Work?by Isaiah David
RV Refrigerator Definition
Nearly all household refrigerators are powered by an electric pump. RV refrigerators, however, are often used in areas where there is no supply of electricity to draw from. Rather than depleting the RV battery to keep the food cold, RVs use a different type of system called a gas absorption refrigerator, which is powered by a propane burner.
Boiling the Ammonia
The refrigeration process starts with the generator, a vessel with water containing dissolved ammonia inside. A burner heats the generator until it reaches the boiling point of ammonia. Since ammonia boils at a lower temperature than water does, the ammonia leaves the generator and wafts up into the condenser. In the condenser, the ammonia starts to cool and eventually forms liquid ammonia, now without water in it.
Cooling it Down
The ammonia flows down from the condenser into a hydrogen-filled chamber called the evaporator. In this low-pressure chamber, the ammonia expands, cooling rapidly as it does. It is the evaporator that creates the cooling action of the refrigerator. A fan blows on the evaporator, cooling down the air as it blows past. This cold air is circulated through the refrigerator.
Back to the Beginning
A device called the absorber sends water trickling through the evaporator. Ammonia dissolves easily in water, but hydrogen does not. The water trickles down with the dissolved ammonia in tow and flows back to the generator, starting the cycle all over again.