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10.1 The refrigerant fluid
10.1.1 Refrigerant families
There are three families of refrigerant fluids:
CFC, HCFC and HFC.
Classifications refer to the chemical composition of
the refrigerants.
HFC - HydroFluoroCarbon indicates that the refrige-
rant is comprised of hydrogen, fluorine, and carbon.
Common HFC refrigerants are R134a.
Environmental demands to protect the ozone layer
and reduce the greenhouse effect have gradually
excluded certain refrigerants from the market. The
ODP and the GWP are the two selection criteria.
The Global-warming potential
The Global-warming potential (GWP) is a relative
measure of how much heat a greenhouse gas traps
in the atmosphere.
The GWP compares the amount of heat trapped by
a certain mass of the gas in question to the amount
of heat trapped by a similar mass of carbon dioxide
(the CO
2
GWP is 1).
The ozone depletion potential
The ozone depletion potential (ODP) of a refrigerant
is the relative amount of degradation it can cause to
the ozone layer.
Since 2001, those refrigerants authorized for auto-
motive A/C applications have no impact on the
ozone layer (ODP=0).
A refrigerant’s GWP is calculated over a specific time
interval: GWP100 refers to a period of 100 years.
The GWP100 for R134a is 1,430; this means that
R134a will trap 1,430 times more heat than carbon
dioxide over the next 100 years.
That is to say, 1 gram of R134a has the same impact
as 1.43 kg of CO
2
over the next 100 years.
A/C players are all working on system evolutions to
reduce the impact of refrigerants on our planet as
much as possible.
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CFC
(ChloroFluoroCarbons)
R12
Dichlorodifluoromethane
CCl
2
F
2
10,890
ODPs and GWPs according to UNEP (United Nations Environment Programme)
1
GWP
100
(Global Warming Potential)
Refrigerant name
Refrigerant family
Molecular
geometry
ODP
(Ozone Depleting Potential)
HCFC Blend
(HydroChloroFluoroCarbons)
R416a
R134a/124/600(59.0/39.5/1.5)
Refrigerant blend
1,100
0.008
HFC
(HydroFluoroCarbons)
R134a
Tetrafluoroethane
CH
2
FCF
3
1,430
0
HFOs
(HydroFluoroOlefin)
R1234yf
Tetrafluoropropene
CF
3
CF=CH
2
4
0
CO
2
R744
Carbon Dioxide
CO
2
1
0
Cl
Cl
C F
F
F
F
C C
F
H
F
H
O=C=O
H
F
F F
C
H F
C=C
Refrigerants families