The energy efficiency and system capacity of systems designed for R-22 is slightly greater using R-22 than the available substitutes.
R-407A is for use in low- and medium-temp refrigeration. Uses a polyolester (POE) oil.
R-407C is for use in air conditioning. Uses a minimum of 20 percent POE oil.
R-407F and R-407H are for use in medium- and low-temperature refrigeration applications (supermarkets, cold storage, and process refrigeration); direct expansion system design only. They use a POE oil.
R-421A is for use in "air conditioning split systems, heat pumps, supermarket pak systems, dairy chillers, reach-in storage, bakery applications, refrigerated transport, self-contained display cabinets, and walk-in coolers." Uses mineral oil (MO), Alkylbenzene (AB), and POE.
R-422B is for use in low-, medium-, and high-temperature applications. It is not recommended for use in flooded applications.
R-422C is for use in medium- and low-temperature applications. The TXV power element will need to be changed to a 404A/507A element and critical seals (elastomers) may need to be replaced.
R-422D is for use in low-temp applications, and is mineral oil compatible.
R-424A is for use in air conditioning as well as medium-temp refrigeration temperature ranges of 20 to 50˚F. It works with MO, alkylbenzenes (AB), and POE oils.
R-427A is for use in air conditioning and refrigeration applications. It does not require all the mineral oil to be removed. It works with MO, AB, and POE oils.
R-434A is for use in water cooled and process chillers for air conditioning and medium- and low-temperature applications. It works with MO, AB, and POE oils.
R-438A (MO-99) is for use in low-, medium-, and high-temperature applications. It is compatible with all lubricants.
R-458A is for use in air conditioning and refrigeration applications, without capacity or efficiency loss. Works with MO, AB, and POE oils.
R-32 or HFC-32 (difluoromethane) is for use in air conditioning and refrigeration applications. It has zero ozone depletion potential (ODP) [2] and a global warming potential (GWP) index 675 times that of carbon dioxide.