Refrigerant Number Representation Method

Inorganic compound: The first digit after R in the code for inorganic compound refrigerants is 7, followed by an integer part of the molecular weight.
Saturated hydrocarbon halide (Freon): The code for Freon is composed of the letter R, followed by the number (m-1) (n+1) (x) B (z). When m=1, (m-1) can be omitted; If z=0, B (z) can be omitted.
Hydrocarbons: Saturated hydrocarbons are also written according to the numbering rules of Freon, except for butane, which is written as R600. In addition, add a letter "a" after the code for isomers, such as R600a for isobutylene.
Unsaturated hydrocarbons and their halogenated element derivatives. Write a "1" after R, and then write the number according to the Freon numbering convention.
Azeotropic refrigerant: In the numbering standard, the first digit after R is specified as 5, and the following two digits are numbered in practical order, such as R500, R501, etc.
Non azeotropic refrigerant: Non azeotropic refrigerant specifies that the first digit after R is 4, and the following two digits are numbered in practical order, such as R400, R401, R407A, R407B, R407C, etc.
Note: To distinguish the extent of damage to the atmospheric ozone layer caused by Freon, R is often replaced by CFC, HCFC, HFC, and HC, respectively.
HC: Hydrocarbons, chlorine free, fluorine free, and pollution-free, can be used as substitutes.
CFC: Chlorinated fluorinated carbon, containing chlorine and no hydrogen, is a public hazard that seriously damages the ozone layer and is prohibited.
HFC: Hydrofluorinated carbon, free of chlorine and environmentally friendly, can be used as a substitute.
HCFC: Hydrochlorofluorocarbon, containing chlorine, hydrogen, and low pollution substances are transitional substances.