Unlike compressor driven residential refrigerators, an absorption refrigerator heats a solution of Ammonia, Hydrogen, Water, and Sodium Chromate which protects the metal. This creates a series of chemical reactions that push the liquids up the tube to the condenser and tubes in the freezer as this liquid hits the tubes the liquid ammonia evaporates into the hydrogen and creates a -20 degree temperature. As the solution continues to evaporate, the temperature rises and as it travels through the freezer and refrigerator sections it draws the warm air out.
