TYPE OF REFRIGERANTS

Research on use of refrigerant is continuously going on due to adverse effect on depletion of ozone layer. The production of many refrigerants will soon end, including R-22 and R-123 in accordance to the requirements of the Montreal Protocol. Suppliers currently offer a range of refrigerants based on chiller type, capacity, and regulatory requirements. The refrigerants can be classified into the following classes:

• Halocarbons: Halocarbon refrigerants are all synthetically produced and were developed as the Freon family of refrigerants. Some of the refrigerants in this class are as follows:− CFCs: R11, R12, R113, R114, R115− HCFCs: R22, R123− HFCs: R134a, R404a, R407C, R410a
• Inorganic refrigerants: Following refrigerants are used as inorganic refrigerants: carbon dioxide, water, ammonia, air, sulphur dioxide.
• Zeotropic refrigerants: A stable mixture of two or several refrigerants whose vapour and liquid phases retain identical compositions over a wide range of temperatures.
• Hydrocarbon refrigerants: Following hydrocarbon gases have been used as refrigerants in industrial, commercial, and domestic applications:− R170, ethane (C₂H₆)− R290, propane (C₃H₃)− R600, butane (C₄H₁₀)− R600a, isobutane (C₄H₁₀)− Blends of the above gases