FREON in HVAC
History of FREON The refrigerants that were used in mechanical refrigeration in the early days were sulphur dioxide, carbon dioxide, ammonia and methyl chloride. The principle behind mechanical refrigeration is that when a compressed air expands, it absorbs heat from the environment. Similarly when a solid is liquified, it absorbs heat as well. The use of these refrigerants caused health hazards to the users when they leaked. This calls for new development of refrigerants that were safe and non-toxic. DuPont led the industry in the invention of safer fluorocarbon refrigerants with the introduction of FREON 12 in 1931. The word "Freon" hence become a trade name for HCFCs and CFCs refrigerants that are sold by this company. This range of products have been used extensively in air conditioning and refrigeration industry. The commercial applications in the early days include the food service industry, food storage, food processing and transportation of goods. Other manufacturers of similar refrigerants came into the picture by introducing their own trade names. The common ones include "GENETRON" from AlliedSignal and "ARCTON" from ICI company. In the early days, the naming used is type of refrigerant followed by the number of compound that make up the refrigerants. The commonly used CFCs and HCFCs refrigerants are CFC-12 and HCFC-22. CFC-12 is also known as Dichlorodifluoromethane which is used in rotary and reciprocating type equipments. It is also used in household and industrial applications such as fridge, freezer and other process-cooling equipments. HCFC-22 is known as Monochlorodifluoromethane and is widely used in the air conditioning industry.
The naming convention of refrigerants have been standardized by the American Society of Heating, Refrigerating and
Air-Conditioning Engineers (ASHRAE). Refrigerants are identified by a number that follows the letter R. They are also
coded with a specific color for easy identification. Most manufacturers follow the color code by using the specific color
on the cyclinder that contain the refrigerant. For instance, the cylinder color of R-12 is White. The cylinder color of
R-22 is Light Green and R-134a is Light(Sky Blue).
Phasing out of CFCs and HCFCs The discovery of the negative effect on the earth's ozone layer has caused the signing of Montreal Protocol in 1987 that called for the phasing out of CFCs and HCFCs. Read out more about the timeline on the phasing out of Freon here. New refrigerants that are being developed by DuPont and use to replace FREON are known as SUVA. SUVA is the trade name of refrigerants that are environmental friendly and are used as their replacement. Do your part by choosing environmental friendly refrigerant in your system design.
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