Most Common Type of Refrigerant in Wall Air Conditioners

How Air Conditioners Work

• A room air conditioner works the same way your refrigerator or your neighbor’s central air unit does. A fluid, called a refrigerant, is alternately pressurized and run through coils of aluminum tubing, allowing de-compression that releases heat. During one side of the cycle, the fluid absorbs heat, cooling the air around it. On the other side, heat radiates off the coils. Fans blow the cool air into the house and hot air out the backside. A pan catches humidity that condenses as the circulating refrigerant cools the air and the precipitate falls down an incline out of the unit. Before systems were sealed, refrigerant leaked -- and evaporated into the atmosphere, necessitating annual inspection and re-charging of refrigerant.

Freon’s Descendents

• Freon, the refrigerant developed by DuPont Flouroproducts, powered many refrigerating systems before it was outlawed by the U.S. Clean Air Act beginning in 1996. Composed of dichlorideflourocarbon, or supplemented carbon tetrachloride, it was generically known as R-12. Room air conditioners built before 1992 were powered with R-12. Beginning with the passage of the Clean Air Act, R-22, a hydrogen chloride fluorocarbon, replaced R-12 in air conditioners. Used in air conditioners after the decline of R-12, R-22 was, in turn, outlawed on a graduated schedule by an amendment to the Clean Air Act, passed in 1992. R-generation refrigerant solutions are similar but not interchangeable, so updating an old air conditioner with R-22 refrigerant is not an option for owners of older machines.

R-410A

• Beginning in 2010, new equipment using alternative refrigerants classified as R-410A filled systems that claimed to be CFC- or HCFC-free. The formula in R-410A is variously marketed under the brand names GENETRON AZ-20, SUVA 410A and Puron. Other related formulations power applications from commercial cooling units all the way down to propellants in bronchiodialators, but R-410A is the most widely used refrigerant for residential units.

What’s In the Box

• Very old air wall conditioners using R-12 cannot be re-charged and likely have been replaced by more efficient, less bulky units. If you bought your unit on sale between 2004 and 2010, it may contain R-22; pre-existing supplies of the refrigerant could be used until 2020. In 2020, R-22 production must cease and servicing of existing machines must use recycled R-22. R-22 filled air conditioner coils for over four decades, however, so plenty of machines use HCFC. R-410A air conditioning units, however, are gaining the majority. After 2020, these new gases and other, related refrigerants will power all but antique wall air conditioners.