It has been over 15 years now since R12 was phased out, yet Tecumseh’s second best selling unit is still the AEA4440AXAXC which is for R12! Not many of these units are installed with R12 but with one of the many “drop in” R12 alternative refrigerants. R134A, the HFC R12 replacement (like R407C which replaces R22) requires 95% POE oil so, in a retrofit, costly multiple oil changes are required. A refractometer is used to confirm 95% POE oil has been achieved before retrofitting.
R22 has now been phased out for all new installations, however, R22 equipment is still being manufactured as a service replacement. R22 new or reclaimed will be around for many years to service R22 equipment but the cost will rise. The list of R22 HFC “drop-in” replacement includes R422B, R422C, and R422D. According to these refrigerant manufactures specs, no oil change or system modifications would be required in most cases. All of these replacements have slightly less capacity then R22, so slightly longer run times may be expected. On marginally sized equipment TXVs and compressors may need to be upsized. As with any retrofit, all of the R22 must be removed, the filter drier must be replaced and a deep vacuum (400 microns or less) should be achieved before retrofitting to a “drop-in” replacement refrigerant. Compressor manufactures retrofit guidelines should also be consulted. Behler-Young can help you with R22 and R22 retrofits.