Manual for Refrigeration Servicing Technicians - UNEP - Division of ...

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Refrigerants
Environmental parameters
Whenever a gas is released into the environment it has some
impact. The most important impacts related to refrigerants are
ozone depletion and global warming.
They are discussed in detail in
Chapter 1 4
Cost and availability
The cost (or retail price) of refrigerants varies widely, with HCFCs
tending to be cheaper, and HFC blends more expensive. Similarly,
the most widely used HCFCs (for example, R22) and the most
common HFCs (e.g. R134a) tend to be most widely available.
Hydrocarbon (HC) refrigerants tend to be less widely available, and
ammonia is normally sourced from specialist suppliers.
In reality, many of these parameters will already have been
addressed, for example, by refrigerant retailers, and through
the availability of components. Whilst there are several hundred
refrigerants currently available, this catalogue of products will have
been filtered down to a more manageable selection.
Most refrigerant retailers will stock around 20 different refrigerants,
whilst manufacturers of components (compressors, valves, heat
exchangers, etc) often limit their range to five to 10 refrigerants,
particularly for non-industrial applications. Often the predominant
selection criteria tend to be: the choice of operating pressures, safety
characteristics and whether the refrigerant has a high or low GWP.
In terms of selection for equipment servicing, the selection depends
upon whether the refrigerant currently in use is restricted or not.
If it is not restricted, then the same refrigerant as indicated on
the nameplate on the equipment should be chosen. If the named
refrigerant is restricted (i.e. due to it being unavailable because of
regulations), then a similar set of considerations need to be applied
as detailed above. The following section outlines the types of
refrigerants that are available.
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