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

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Refrigerant Management
Identification and testing of refrigerants
Is very important to know which refrigerant is in a system in order that
correct refrigerant can be used when work is carried out on the system.
Refrigerants may be identified by the following methods:
• Refrigerants stamped on unit data plate, thermostatic expansion
valve, or compressor
• Standing pressure
• Refrigerant Identifier – a portable electronic device that allow the
reliable identification or detection of percentage composition
(not all) of CFCs, HCFCs, HFCs, hydrocarbons (HC) and air
content.
In the case of hermetic systems that have not be opened (i.e., no
sign of post-manufacture manipulation of the system, such as
recent brazing or piercing valves), the first method is adequate. In
other systems, the last method should ideally be used, since it is
the most reliable. If a system has previously been broken into, it is
possible that a retrofitted refrigerant may have been charged into
the system. In this case, the marking on the name plates may not
reflect this, and the standing pressure may be the same for the
original and the new refrigerant.
Testing considerations include:
Test refrigerant for contamination 4
Test oil contamination 4
Checking of refrigerant cylinders 4
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