Nomenclature For Refrigerants

The refrigerant code was first specified for Freon, and at the time of publication, it was the standard established by the American Heating and Refrigeration Engineering Association in 1967 (ASHRAE Standard 34-67). The numbering method of this standard is to associate the refrigerant code with its species and chemical composition. As long as its chemical molecular formula is known, its code can be written. The code is composed of the letter "R" and the number after it. R represents the refrigerant (refrigeration medium) "Refrigerant", and previously F represented "Freon". When publishing, the internationally recognized R was used to name the refrigerant.
(1) Inorganic compound refrigerant
If ammonia is named: R717 (molecular formula NH3)
'7' represents an inorganic compound class, with 17 being the integer part of its molecular weight.
(2) Freon refrigerant
Freon is a general term for the derivatives of halogenated elements in saturated hydrocarbons (alkanes).
The molecular formula of saturated hydrocarbons is CmH2m+2. When H2m+2 is partially or completely replaced by fluorine, chlorine, or bromine, the resulting derivative is CmHnFxClyBrz, which is the general molecular formula of Freon, and n+x+y+z=2m+2.
For the methane system, because m=1, n+x+y+z=4
For the ethane series, because m=2, n+x+y+z=6
The code for Freon is composed of R (m-1) (n+1) (x) B (z). If z=0, then B can be omitted, for example:
Difluorochloromethane, with the molecular formula CHF2Cl, m-1=0, n+1=2, x=2, z=0, is therefore codenamed R22.
Difluorodichloromethane, with the molecular formula CF2Cl2, m-1=0, n+1=1, x=2, z=0, is therefore codenamed R12.
(3) Saturated hydrocarbons
The numbering rule of the code is the same as that of Freon.
For example, methane is R50
Ethane is R170
Propane is R290
But butane is written as R600 instead of following the above rules.
In addition, if it belongs to an isomer, add the letter "a" after the code or a number above the single digit, such as R152a for isobutane and R601 for isobutane.
(4) Cyclic compound
Cyclic organic compounds are written by adding a letter "C" after R and following the numbering rules of Freon,
For example, writing RC316 for hexafluorodichlorocyclobutane
Writing RC318 et al. for octafluorocyclobutane.
(5) Unsaturated hydrocarbons and their halogenated element derivatives
This type of refrigerant is first written with a "1" after R, and then written according to the numbering rules of Freon.
For example, R1150 for ethylene
Propylene is R1270
Difluorodichloroethylene is R1112a, etc.
(6) Azeotropic refrigerant
A refrigerant composed of two or more immiscible single component substances mixed at room temperature in a certain mass or volume ratio. Its properties are similar to that of a single refrigerant