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PREFIXES, DECODING AND CODING OF REFRIGERANTS
D R . AB D U A L H
A D I N. K
H A L I FA
PREFIXES OF REFRIGERANTSome of the most common refrigerants’ prefixes are
الكيميائي االسم Prefixes
components
كلوروفلوروكاربون Chlorofluorocarbon CFC Cl, F and C هايدروكلوروفلوروكارب
ونHydrochlorofluorocarbon HCFC H, Cl, F and C
هايدرويروموفلوروكاربون
Hydrobromofluorocarbon HBFC H, Br, F and C
هايدروفلوروكاربون Hydrofluorocarbon HFC H, F and Cهايدروكاربون Hydrocarbon HC H and C
مشبعة هيدروكاربونات Perfluorocarbon PFC F and Cالهالونات Halon Halon Br, Cl (in some),
F, H (in some), C
DECODING OF REFRIGERANT NUMBERThe prefix describes the kinds of atoms
in a particular molecule, and the next step is to calculate the number of each type of atom. The key to the code is to add 90 to the number; the result shows the number of
C, H, and F atoms
CARBON BONDSEvery carbon atoms have 4 bonds, the following equation
can be used to calculate the number of bonds in one or more carbon atoms
#Bonds= 2×#C+2If there are two carbon atoms the number of bonds are
equals to#Bonds= 2×2+2= 6Foe 3 C#Bonds= 2×3+2=8And so on
EXAMPLEHCFC- 141
#C= 2#H=3#F=1The remains bonds of C should have Chlorine atoms #Cl= #bonds - #H - #F #Cl= 2×2+2-3-1 = 6 – 4 = 2
Ref-#
+ 90 = C H F
141 + 90 = 2 3 1
Then What is the chemical composition of HCFC-141 HCFC-141a and HCFC-141b ???The “letter ” at the end describes how these atoms
are arranged; different “isomers” contain the same atoms, but they are arranged differently.
R-141 CONTAINS THE FOLLOWING ATOMS
Cl F H C35.5 19 1 12
C
C
H
H
H
F
Cl
Cl
19
35.5
35.5
1
1
1
1+1+1= 390=35.5+35.5+19 90-3= 87
R-141 CONTAINS THE FOLLOWING ATOMS
Cl F H C35.5 19 1 12
C
C
H
H
H
F
Cl
Cl
19
1
35.5 1
1
35.5
35.5+1+1= 37.555.5=1+35.5+19 55.5-37.5= 18
R-141 CONTAINS THE FOLLOWING ATOMS
Cl F H C35.5 19 1 12
C
C
H
H
H
F
Cl
Cl
35.5
1
35.5 1
1
19
19+1+1= 2172=1+35.5+35.5 72-22= 51
CCl Cl
F
H
C
H
H
35.5
1
19
1
35.5
1
35.5+1+1= 37.555.5= 1+35.5+19
CCl F
Cl
H
C
H
H
35.5
1
35.5
1
19
1+19+1=21
1
72=35.5+35.5+1
CCl H
Cl
F
C
H
H
35.5
19
35.5
1
1
1
1+1+1=390=19+35.5+35.5
55.5-37.5=18 72-21=51
90-3=87
HCFC-141
HCFC-141a
HCFC-141b
CHFClCH2Cl CHCl2CH2Cl
CFCl2CH3
CFC-12 does not have any isomers, since it contains only one C. In addition, there is no need to number the carbons
MOLECULES WITH THREE-C ATOMSMolecules with three-C atoms are more complicated
to name, such as HCFC-225ca. The first letter designates the atoms attached to
the middle C atom, and the second letter designates decreasing
symmetry in atomic weights of atoms attached to the outside C atoms.
Unlike 2C chains, however, the most symmetric distribution is the “a” isomer, instead of omitting the letter entirely.
The code letters for the atoms on middle C are
C C C
Cl
Cl
a
C C C
F
Cl
b
C C C
F
F
c
C C C
H
Cl
d
C C C
F
H
e
C C C
H
H
f
EXAMPLEHCFC-225ca
#C= 3#H= 1#F = 5The remains bonds of C should have Chlorine atoms #Cl= #bonds - #H - #F #Cl= 2×3+2-1-5 = 8 – 6= 2
Ref-#
+ 90 = C H F
225 + 90 = 3 1 5
THE LETTER C MEANS
C C C
F19
F19
F19
F19 Cl
35.5
Cl 35.5
H1
F19
57 72 72-57=15
CF3CF2CHCL2CClF2CF2CHClF
HCFC-225ca HCFC-225cb
REFRIGERANTS CODINGCFC-12
HCFC-22HCFC-123 PFC-218
HC-170
HFC-329CFC-13B1
R-717HC-601
R507
R407A
HC-1150
PFC-218
Since a large number of refrigerants have been developed over the years for a wide variety of applications, a numbering system has been adopted to designate various refrigerants. From the number one can get some useful information about the type of refrigerant, its chemical composition, molecular weight etc.
SERIES NUMBERING FOR REFRIGERANT CLASSES
000 Methane-based100 Ethane-based200 Propane-based300 Cyclic organic400 Zeotropes500 Azeotropes600 Organic700 Inorganic1000 Unsaturated organic
This numbering system also allows refrigerants to be grouped into series. Below is an explanation of the various refrigerant groups.
METHANE, ETHAN, PROPANE BASES , CYCLIC ORGANIC AND UNSATURATED ORGANIC The number assigned to each refrigerant is related to its chemical composition and the system has been formalized as ASHRAE Standard 34. The numbering system rules are as follows:
1000 100 10 1 Br #Unsaturated organic
C-1 H+1 F If the refrigerant contains bromine
atoms
Number of bromine
atoms
EXAMPLESFor example CHF3
The refrigerant is saturated since the number of atoms equals to the number of carbon bonds
Since the refrigerant contains C, H and F the prefixes is HFC-23
1000 100 10 1 Br #Unsaturated organic
C-1 H+1 F If the refrigerant contains bromine
atoms
Number of bromine
atoms
000 1-1=0 1+1=2 3 ---- ------
CHCl 2CF 3
HCFC – 123
1000 100 10 1 Br #Unsaturated organic
C-1 H+1 F If the refrigerant contains bromine
atoms
Number of bromine
atoms
000 2-1=1 1+1=2 3 ---- ------
CF 3CF 2CF 3
• It is a Per fluorinated refrigerant thus, the prefixes is PFC, and the refrigerant is PFC-218
1000 100 10 1 Br #Unsaturated organic
C-1 H+1 F If the refrigerant contains bromine
atoms
Number of bromine
atoms
000 3-1=2 0+1=1 8 ---- ------
CBrF3
CFC-13 B1
1000 100 10 1 Br #Unsaturated organic
C-1 H+1 F If the refrigerant contains bromine
atoms
Number of bromine
atoms
000 1-1=0 0+1=1 3 Br 1
C2H6
HC- 170
1000 100 10 1 Br #Unsaturated organic
C-1 H+1 F If the refrigerant contains bromine
atoms
Number of bromine
atoms
000 2-1=1 6+1=7 0 --- ---
ZEOTROPIC AND AZEOTROPIC BLENDS.As a special case, the R-400 series is made up of zeotropic blends (those where
the boiling point of constituent compounds differs enough to lead to changes in relative concentration because of fractional distillation)
and the R-500 series is made up of so-called azeotropic blends.
The rightmost digit is assigned arbitrarily by ASHRAE, an industry organization.
MISCELLANEOUS ORGANIC COMPONENTSMiscellaneous organic compounds shall be assigned numbers in
the 600 series in decadal groupsFor the saturated hydrocarbons with 4 to 8 carbon atoms, the
number assigned shall be 600 plus the number of carbon atoms minus 4
Example
Butane CH3CH2CH2CH3HC – 600+( 4-4)== HC-600
Isobutene (CH3)2CHCH2CH3HC – 600 +(5-4)= HC - 601
ORGANIC COMPONENTSThese are designated by number 7 followed by the molecular weight of
the refrigerant
Example NH3R-700+( 14+3)= R-717
H2OR-718
CO2R-744
UNSATURATED REFRIGERANTUnsaturated hydrocarbons are hydrocarbons that have double
or triple covalent bonds between adjacent carbon atomsExample C2H4
Number of carbon bonds is 6, number of atoms are 4, 2 bonds are free
C
C
H
H
H
H??
Propene CH3CH=CH 2
Carbon bonds = 2×3+2 = 8# atoms 6 unsaturated
HC- 1270
1000 100 10 1 Br #Unsaturated organic
C-1 H+1 F If the refrigerant contains bromine
atoms
Number of bromine
atoms
1 3-1=2 6+1=7 0 --- --
Thank You For
Listening
