You may have an Air Conditioning unit at your home that uses R22 refrigerant. If your home inspector or HVAC professional has mentioned this to you, here is what you need to know.
Basically, R22 refrigerant (also called HCFC-22 or Freon) was widely used in many air conditioners up until about 2010. This product is being phased out of production due to environmental concerns from the EPA (read more here). If your AC unit is older than 2010, it likely still has R22 inside. You can look up the age here. The concern is that the cost to add R22 into a unit for repairs or maintenance will likely be expensive, and that cost will only increase with time as there isn’t a large supply. While the AC may be working just fine, it is important to understand costs to repair may not be feasible. Upgrades to a newer air conditioning system will likely be the course of action.
Most newer air conditioners use a more environmentally friendly refrigerant product called R-410A. You can easily find out which product you have by reading the manufacturers data plate that is mounted on the unit.
This is HCFC-22 (Commonly R22 or Freon)
This is R-410A, the new standard in Refrigerant.