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

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Refrigerant Management
Refrigerant conservation
Refrigerant conservation is part of a refrigerant management
strategy. It is an effort to extend the lifetime of used refrigerant by
establishing methods to contain, recover, recycle, and reclaim for
the purpose of reuse and minimising emissions to the environment.
Containment is important not only to protect the environment,
preventing refrigerant emissions, but also to ensure proper
functioning and efficiency of air-conditioning and refrigeration
systems. Cooling systems are designed as sealed units to provide
long term operation with a fixed charge of refrigerant. Conservation
is affected by the design, installation, service and disposal of
the refrigerating system. Guidelines and standards are being
developed and updated in several countries with consideration to
environmental matters and improved conservation.
Refrigerant emissions
Refrigerant emissions to the atmosphere often occur without
identification of the cause. However, the identification of the
sources of refrigerant leaks is necessary to limit emissions.
Refrigerant emissions occur because of the following:
• Tightness degradation due to temperature variations, pressure
cycling, and vibrations that can lead to unexpected leaks
• Component failures from poor construction or faulty assembly
• Losses due to refrigerant handling during maintenance (e.g.
charging the system), and servicing (e.g. opening the system
without previously recovering the refrigerant)
• Accidental losses (e.g. natural disasters, fires, explosions,
sabotage, and theft)
• Losses at equipment disposal that is due to venting, rather than
recovering refrigerant at the end of the system’s life
When designing, installing and servicing refrigeration systems,
technicians should keep these causes in mind, and work on
systems in ways that avoid them occurring.
Containment
Containment is the general concept of retaining the refrigerant
within the equipment by having leak-proof joints and seals,
pipelines, etc, and handling the refrigerant in a manner that
minimises refrigerant releases.
Leak detection is a basic element of containment and must take
place in manufacturing, commissioning, maintenance and servicing
of refrigerating and air-conditioning equipment, as it allows
measuring and improving conservation of refrigerants.
There are three general means of identifying whether refrigerant may be
leaking from a system:
a) Global methods - such as fixed refrigerant detectors, which
indicate that there is the presence of refrigerant, but they
do not actually locate a leak. They are useful at the end of
manufacturing and each time the system is opened up for repair
or retrofit.
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