a) Become familiar with the equipment and its operation.
b) Isolate system electrically.
c) Before attempting the procedure ensure that :mechanical handling equipment
is available, if required, for handling refrigerant cylinders; all personal protective
equipment is available and being used correctly; the recovery process is
supervised at all times by a competent person; recovery equipment and
cylinders conform to the appropriate standards.
d) Pump down refrigerant system, if possible.
e) If a vacuum is not possible, make a manifold so that refrigerant can be
removed from various parts of the system.
f) Make sure that cylinder is situated on the scales before recovery takes place.
g) Start the recovery machine and operate in accordance with manufacturer's
instructions.
h) Do not overfill cylinders. (No more than 80 % volume liquid charge).
i) Do not exceed the maximum working pressure of the cylinder,even
temporarily.
j) When the cylinders have been filled correctly and the process completed,
make sure that the cylinders and the equipment are removed from site promptly
and all isolation valves on the equipment are closed off.
k) Recovered refrigerant shall not be charged into another refrigeration system
unless it has been cleaned and checked.
10 LABELLING
Equipment shall be labelled stating that it has been de-commissioned and
emptied of refrigerant.The label shall be dated and signed.
Ensure that there are labels on the equipment stating the equipment contains
flammable refrigerant.
11 RECOVERY
When removing refrigerant from a system, either for servicing or
decommissioning, it is recommended good practice that all refrigerants are
removed safely. When transferring refrigerant into cylinders, ensure that only
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appropriate refrigerant recovery cylinders are employed. Ensure that the
correct number of cylinders for holding the total system charge are available.All
cylinders to be used are designated for the recovered refrigerant and labelled
for that refrigerant (i.e. special cylinders for the recovery of refrigerant).
Cylinders shall be complete with pressure relief valve and associated shut-off
valves in good working order. Empty recovery cylinders are evacuated and, if
possible, cooled before recovery occurs.
The recovery equipment shall be in good working order with a set of
instructions concerning the equipment that is at hand and shall be suitable for
the recovery of flammable refrigerants.In addition,a set of calibrated weighing
scales shall be available and in good working order. Hoses shall be complete
with leak-free disconnect couplings and in good condition. Before using the
recovery machine, check that it is in satisfactory working order, has been
properly maintained and that any associated electrical components are sealed
to prevent ignition in the event of a refrigerant release. Consult manufacturer if
in doubt.
The recovered refrigerant shall be returned to the refrigerant supplier in the
correct recovery cylinder,and the relevant Waste Transfer Note arranged. Do
not mix refrigerants in recovery units and especially not in cylinders.
If compressors or compressor oils are to be removed, ensure that they have
been evacuated to an acceptable level to make certain that flammable
refrigerant does not remain within the lubricant. The evacuation process shall
be carried out prior to returning the compressor to the suppliers. Only electric
heating to the compressor body shall be employed to accelerate this
process.When oil is drained from a system,it shall be carried out safely.
Competence of service personnel
General
Special training additional to usual refrigerating equipment repair procedures is
required when equipment with flammable refrigerants is affected.
In many countries, this training is carried out by national training organisations
that are accredited to teach the relevant national competency standards that
may be set in legislation.
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