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

3
Refrigerant Management
CHAPITRE 3
PAGE 16
Typical multi-pass system
• The multiple pass method re-circulates the recovered refrigerant
many times through filter-driers. After a certain period of time
or number of cycles, the refrigerant is transferred into a storage
cylinder. Multiple-passes method recycling takes longer,
but depending on the refrigerant level of contamination and
moisture it may be essential, for example, if it is particularly dirty.
This is shown in the diagram:
MANIFOLD
PRE-FILTER
RECOVERY
UNIT
FILTER
DRIER
SYSTEM
RECEIVER
&
PURGE UNIT
MOISTURE
INDICATOR
Typical multi-pass system
LIQUID
PUMP
AC UNIT
OIL
SEPARATOR
ACCUMULATOR
OIL
DRAIN
CONDENSER
RECOVERY
CYLINDER
RECYCLE
SOLENOID
FILTER
DRIER
COMPRESSOR
OIL
DRAIN
OIL
SEPARATOR
RECYCLE LOOP
OIL RETURN
Refrigerant recovery and recycling equipment
The purpose of refrigerant recovery and recovery/recycling
equipment is to help prevent emissions of refrigerant by providing
a means of temporarily storing refrigerants that have been removed
from systems undergoing service or disposal. Such equipment is
used to temporarily store recovered refrigerant until the system
undergoing repair is ready to be recharged or is prepared for
disposal. Refrigerant recovery equipment may have the ability to
store (recovery only) or the added capability of recycling (recovery
and recycling) refrigerants. The temporary storage capability of the
equipment prevents the release of refrigerants into the atmosphere
that may otherwise exist if the refrigeration and air-conditioning
equipment were opened to the atmosphere for servicing.
The use of refrigerant recovery and recycling equipment is an
essential means of conserving refrigerant during servicing,
maintenance, repair, or disposal of refrigeration and air-conditioning
equipment. Refrigerant recovery and recycling equipment could
be made available to service technicians in every sector. Note that
due to incompatibility issues and the array of refrigerants used
in different sectors, refrigerant recovery/recycling equipment
intended for use with one type of air conditioning system, such as
motor vehicle air conditioners, may not be adequate to service airconditioning
and refrigeration equipment in the domestic, unitary,
or commercial refrigeration and air-conditioning sectors. The types
of refrigerants used in these sectors vary and all recovery/recycling
equipment is not capable of meeting the same requirements.
This is very important to users to ensure that their recovery
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