2. PREFIXES OF REFRIGERANT
Some of the most common refrigerants’ prefixes are
االسمالكيميائيPrefixescomponents
كلوروفلوروكاربونChlorofluorocarbonCFCCl, F and C
هايدروكلوروفلوروكاربونHydrochlorofluorocarbonHCFCH, Cl, F and C
هايدرويروموفلوروكاربونHydrobromofluorocarbonHBFCH, Br, F and C
هايدروفلوروكاربونHydrofluorocarbonHFCH, F and C
هايدروكاربونHydrocarbonHCH and C
هيدروكاربوناتمشبعةPerfluorocarbonPFCF and C
الهالوناتHalonHalonBr, Cl (in some), F,
H (in some), C
3. DECODING OF REFRIGERANT NUMBER
The 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
4. CARBON BONDS
Every 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+2
If there are two carbon atoms the number of bonds are
equals to
#Bonds= 2×2+2= 6
Foe 3 C
#Bonds= 2×3+2=8
And so on
5. EXAMPLE
HCFC- 141
#C= 2
#H=3
#F=1
The 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
6. 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.
7. R-141 CONTAINS THE FOLLOWING ATOMS
ClFHC
35.519112
C
C
H
H
H
F
C
l
C
l
19
35.5
35.5 1
1
1
1+1+1= 390=35.5+35.5+19
90-3= 87
8. R-141 CONTAINS THE FOLLOWING ATOMS
ClFHC
35.519112
C
C
H
H
H
F
C
l
C
l
19
1
35.5 1
1
35.5
35.5+1+1= 37.555.5=1+35.5+19
55.5-37.5= 18
9. R-141 CONTAINS THE FOLLOWING ATOMS
ClFHC
35.519112
C
C
H
H
H
F
C
l
C
l
35.5
1
35.5 1
1
19
19+1+1= 2172=1+35.5+35.5
72-22= 51
10.
11. 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
12. CFC-12 does not have any isomers,
since it contains only one C. In
addition, there is no need to number
the carbons
13. MOLECULES WITH THREE-C ATOMS
Molecules 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.
14. 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
15. EXAMPLE
HCFC-225ca
#C= 3
#H= 1
#F = 5
The 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
16. THE LETTER C MEANS
C C C
F
19
F
19
F
19
F
19
Cl
35.5
Cl
35.5
H
1
F
19
57 72 72-57=15
CF3CF2CHCL2
CClF2CF2CHClF
HCFC-225caHCFC-225cb
18. 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.
19. SERIES NUMBERING FOR REFRIGERANT
CLASSES
000 Methane-based
100 Ethane-based
200 Propane-based
300 Cyclic organic
400 Zeotropes
500 Azeotropes
600 Organic
700 Inorganic
1000 Unsaturated organic
This numbering system also allows refrigerants to be grouped into series.
Below is an explanation of the various refrigerant groups.
20. 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 #
Unsaturate
d organic
C-1 H+1 F If the refrigerant
contains bromine atoms
Number of
bromine
atoms
21. EXAMPLES
For 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 #
Unsaturate
d organic
C-1 H+1 F If the refrigerant
contains bromine atoms
Number of
bromine
atoms
000 1-1=0 1+1=2 3 ---- ------
22. CHCl 2CF 3
HCFC – 123
1000 100 10 1 Br #
Unsaturate
d organic
C-1 H+1 F If the refrigerant
contains bromine atoms
Number of
bromine
atoms
000 2-1=1 1+1=2 3 ---- ------
23. 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 #
Unsaturate
d organic
C-1 H+1 F If the refrigerant
contains bromine atoms
Number of
bromine
atoms
000 3-1=2 0+1=1 8 ---- ------
24. CBrF3
CFC-13 B1
1000 100 10 1 Br #
Unsaturate
d 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
25. C2H6
HC- 170
1000 100 10 1 Br #
Unsaturate
d organic
C-1 H+1 F If the refrigerant
contains bromine atoms
Number of
bromine
atoms
000 2-1=1 6+1=7 0 --- ---
26. 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.
27. MISCELLANEOUS ORGANIC COMPONENTS
Miscellaneous organic compounds shall be assigned numbers in the 600
series in decadal groups
For 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 CH3CH2CH2CH3
HC – 600+( 4-4)== HC-600
Isobutene (CH3)2CHCH2CH3
HC – 600 +(5-4)= HC - 601
28. ORGANIC COMPONENTS
These are designated by number 7 followed by the molecular weight of the
refrigerant
Example NH3
R-700+( 14+3)= R-717
H2O
R-718
CO2
R-744
29. UNSATURATED REFRIGERANT
Unsaturated hydrocarbons are hydrocarbons that have double or triple
covalent bonds between adjacent carbon atoms
Example C2H4
Number of carbon bonds is 6, number of atoms are 4, 2 bonds are free
C
C
H
H
H
H
??
30. Propene CH3CH=CH 2
Carbon bonds = 2×3+2 = 8
# atoms 6 unsaturated
HC- 1270
1000 100 10 1 Br #
Unsaturate
d organic
C-1 H+1 F If the refrigerant
contains bromine atoms
Number of
bromine
atoms
1 3-1=2 6+1=7 0 --- --
