What is R22 Refrigerant or Freon?
R22 refrigerant is one of the most commonly used refrigerants in the air conditioning systems. R22 is the short name for the halocarbon compound CHClF2 (monochlorodifluoromethane), which is used as the refrigerant. R stands for the refrigerant. In the number “22" second “2" denotes the number of the fluorine atoms in the compound.
The boiling point of R22 is -40.8 degree Celsius (-41.4 degree F). Due to its low boiling point this refrigerant was initial developed for the low temperature applications like domestic and farm freezers and in industrial refrigeration applications. Even at present R22 is extensively used in the industries for liquefaction of the gases like chlorine, for supplying chilled water to various processes, machines, chillers of central air conditioning systems, etc.
One of the most common uses of R22 is in the domestic air conditioners like window AC, split AC, packaged AC and also in number of central air conditioning systems. R22 is non-toxic and it is non-flammable that makes this refrigerant highly safe for the domestic and industrial purposes.
The discharge temperature of R22 is quite high, hence the degree of superheat in the systems using this refrigerant should be minimum. The compression ratio for the systems using this refrigerant should also be low, and if it is high intercooling between the two stages of the compression should be kept.
R22 refrigerant is easily miscible with the oil at condenser temperature, but at the evaporator temperature it tends to get separated from the oil, however, if the evaporator and the suction piping are designed properly, no such problem occurs. In case of the flooded evaporators the oil gets separated from R22 so there should be provision for separating the oil. It the system is being used for the developing low temperature, the oil separators should be installed to remove the oil from the evaporator. In the present days some good synthetic lubricants have been developed that don’t separate from R22.