You probably don’t give your air conditioning in South Miami, FL more thought than necessary: as long as you schedule regular maintenance, change the air filter once a month during the warm months, and have professionals do prompt repairs when it malfunctions, your AC should continue to work for you for many years.
However, you can benefit from some extra knowledge about how an air conditioner operates, since it can help you understand why certain malfunctions occur. A key part of understanding AC operation is knowledge of the refrigerant inside it, the chemical blend that allows the system to move heat from inside your home to outside your home. Here’s what you should know about refrigerant types, courtesy of our AC specialists at Air On Demand.
The Development of Refrigerant
Willis Carrier invented the first electromechanical air conditioning unit in 1902, and it used water as refrigerant. However, water has too high a boiling point for energy efficient performance, so other chemical soon replaced it. The early air conditioners used ammonia, methyl chloride, or propane. All of these worked more efficiently at changing from liquid to gas and back again, but they had serious drawbacks: they were either flammable or toxic, and leaks could lead to dangerous accidents. This made ACs unsuitable for home use.
In 1928, the first non-flammable, non-toxic refrigerant blend was created, R-22.
The dominant blend across the globe is R-22 (the name refers to the molecular composition of the chemical), a hydrochlorofluorocarbon. However, R-22 is a greenhouse gas and contributes to ozone depletion, so in the United States it is being gradually phased out with the goal of 99.5% elimination by 2020. The main replacement blend—most likely the blend cycling through your air conditioner right now—is R-410A, also known as Puron and EcoFluor R410—is a mix of difluoromethane and pentafluoroethane. Because R-410A contains no fluorocarbons, it does not deplete the ozone layer.
Refrigerant Leaks and Recharging
Whatever refrigerant flows through your AC, it has a fixed level—called the refrigerant’s “charge”—that cycles in a closed loop through the system. The process of evaporation and condensation that provides you with cooling does not use up the refrigerant charge. However, leaks can occur: punctures in the coils, loose connections, breaks in the compressor. Leaking refrigerant will cause ice to develop along the indoor coils, and when this happens you need to call for professional repairs. Not only do you need an expert to seal the leaks, but the expert must use the proper refrigerant blend to replace the lost charge.