R22, also called Freon, is a type of refrigerant that was used up to the beginning of this year. It started getting phased out a few years ago because of how harmful it is for the environment. Manufacturing of R22 was banned in January 2021. Sometimes you can still find recycled R22 to recharge older air conditioners with, but it makes the most sense to upgrade your air conditioner if yours is still using R22 refrigerant.