For many years R-22 has been the most dominant refrigerant on the market. Used in both commercial and domestic air conditioning applications, R-22 replaced earlier CFC refrigerants and became the most widely used Freon in modern air conditioning. But although R-22 can still be found in many systems still in operation today, its use has become less practical and in decline as it faces its own pending extinction.
Like the CFC refrigerants before it, R-22 will soon be completely phased out with r22 replacments. Manufacturers have been prohibited from producing new systems that contain R-22 since 2010 and all production and imports will be illegal in 2020. Since its targeted demise, the air conditioning industry has been busy preparing by designing new systems and retrofitting those currently in use to make way for a new wave of refrigerants.
R-22 is a HCFC refrigerant meaning it contains hydrogen, chlorine, fluorine, and carbon. The chlorine found in R-22 has been deemed harmful to the enviornment and a major cause of ozone depletion. Just one chlorine atom released to the atmosphere can attack up to 100,000 ozone molecules, allowing more ultraviolet light to reach the earth’s surface. New systems now contain less harmful alternatives, most commonly Hydrofluorocarbon – or HFC for short – refrigerants.
HFC refrigerants are the most widely used in newly manufactured systems today. HFC’s contain hydrogen, fluorine, and carbon but lack the harmful chlorine atoms found in earlier refrigerants. HFC’s have zero ozone depletion potential and though they can contribute to global warming if vented to the atmosphere, are considered a far safer alternative. Most R-22 systems are replaced with systems that contain R-407-C, R-404a, and R-41oa HFC refrigerants. Among these, R-41oa has been the most favored replacement. R-41oa lacks the harmful effects of previous CFC and HCFC refrigerants and is also a more energy efficient alternative. Because R-41oa operates at extemely low pressures, it allows for a greater amount of heat transfer to occur. This requires the system to do less work, operate less frequently, and saves energy costs. The low operating temperatures of R-41oa however, also create higher system pressures. R-41oa systems operate at pressures 40-70% higher than R-22 containing systems. As a result, retrofitting a system that ran on R-22 to run on R-41oa can be a costly undertaking.
A system retrofit often involves changing out critical components like the compressor and condenser and evaporator coils to withstand the increased operating pressures. ACR refrigerant tubing may also need replacement with thicker gauge copper. R-41oa systems also require different lubrication. While R-22 systems use mineral oil, R-41oa refrigerant requires polyol ester oil. Removing the residual oil from a R-22 system can be a painstaking task that takes a technician a great deal of time and adds to retrofit costs.
For these reasons many air conditioning systems that experience leaks or major component failures are replaced instead of retrofitted. Often the cost to retrofit a system is not worth the expense and most technicians will recommend a new system. Add to this the high cost of R-22 Freon since the manufacture phase out in 2010, and continually recharging a leaking R-22 system can quickly become a cost endeavor.