If a system has R22 in it already you cannot use a replacement refrigerant to simply add to the R22. For one, R 22 is its own refrigerant whereas the replacement refrigerants are made up of several different kinds of refrigerant designed to mimic operating pressures/temperatures of R 22. Equipment manufacturers will also tell you that unless the oil being used in your HVAC system is POE oil you cannot use a R22 replacement refrigerant in the system in most cases (M099 is the exception). Most of the older systems use mineral oil that is less viscous than POE oil, and the mineral oil does not work well with the new R22 replacement refrigerants. If the compressor has been replaced recently or the system is relatively new it may have POE oil in it in which case adding a R22 replacement refrigerant to a system that has little to no refrigerant in it is a viable solution that should be discussed with the homeowner.
- If the system is still under warranty no manufacturer’s will warranty the system if you use a replacement R22 refrigerant, as their systems have often not undergone testing with the various replacement refrigerants
- You should never under any circumstances add replacement refrigerant to a system that has any R22 refrigerant left in it.
If the system uses POE oil than you can talk with the customer about removing the existing R22 and using a cheaper R22 replacement refrigerant such as R407C.
Despite what you see on the posted on you tube/internet it is not advisable to try to add POE oil to a system without completely removing all mineral oil as the oil mixture will gum up metering devices.
If your compressor fails and you elect to change out the compressor as opposed to changing out the entire system, it may be wiser to change out the type of refrigerant to the replacement R22 refrigerants such as R407c. Doing so could save you a considerable amount should your system develop a leak in the years ahead. All new compressors use POE oil and are compatible with R407c and most other R22 replacement refrigerants.
Below you can find different R22 replacement refrigerants and the+/- of each. Legacy Air currently only offers R407c as our choice for an R 22 replacement refrigerant and we do carry it on our trucks. We do not normally carry M099, but will acquire some and install for the customer upon their request in conjunction with a leak repair. Cost is $50 per lb + 1.5 hours labor.
The Facts About Alternative Refrigerants
- They void all manufacturer warranties
- They are best suited for condensers and heat pumps out of warranty
- They are non-ozone-depleting hydrofluorocarbons (HFCs)
- When given an ASHRAE number (designated with an R-), they have been reviewed by the industry standards committees and a safety classification has been assigned
- They should not be combined with R-22 refrigerant or other gases; never mix refrigerants