Lubrication The most important part in a compressor used in refrigeration or air conditioning. Choosing the right lubricant depends on many factors, including the requirements of the specific type of compressor and temperature limits and the type of refrigerant.
One of the most interesting factors in the refrigeration and air conditioning systems is the solubility characteristics of the refrigerants in oils. All refrigerant fluids are soluble to a limited extent in oil. In a refrigeration or air conditioning system, the oil is never completely free of refrigerant, just as the refrigerant is never completely free of oil.
The oils used in refrigeration system compressors differ appreciably from those used in other types of equipment. Although the lubricant is required only in the compressor, it also circulates through the entire system along with refrigerant, with which it is in close contact during the temperature and pressure variations that occur in the refrigeration cycle.
