R-22 is the “old” refrigerant or “Freon” that has been used for many years in central air conditioners. Over the past decade, R-22 has been phasing out and replaced with R-410A. R-410A is more environmentally friendly. As of 2020, R-22 will no longer be permitted to be manufactured or imported into the USA.

An existing air handler or coil can be retrofitted to work with R-410A by replacing the expansion valve.  However, R-410A operates at a higher pressure and can cause older coils to develop leaks after the change over.  Consider the age of your coil when changing to R-410A.  It may be a good time to change your entire system.