Automobile Air Conditioning Due to varying conditions of heating, ventilating, cooling and dehumidification in atmosphere at various places, the air conditioning of automobiles is very essential. To maintain human comfort and improve internal atmosphere in an enclosed space, proper control of freshness temperature, humidity and cleanliness of air required. In an automobile the air conditioning system involvs two main processes of heating and cooling. In the heating system, warm water from the engine cooling system is used. The heat required to warm the automobile is generally provided by circulating warm water through heating coil. For producing cooling effect the evaporator coil operated by refrigeration system is placed inside the chamber of automobile. The components used for producing cooling effect, its working are discussed here