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Ensure that the refrigeration system is earthed prior to charging the system with refrigerant. Label the system
when charging is complete (if not already).
Extreme care shall be taken not to overfill the refrigeration system. Prior to recharging the system it shall be
pressure tested with OFN. The system shall be leak tested on completion of charging but prior to
commissioning. A follow up leak test shall be carried out prior to leaving the site.
Q. Decommissioning
a) Before carrying out this procedure, it is essential that the technician is completely familiar with the
equipment and all its detail. It is recommended good practice that all refrigerants are recovered safely. Prior
to the task being carried out, an oil and refrigerant sample shall be taken in case analysis is required prior to
re-use of reclaimed refrigerant. It is essential that electrical power is available before the task is commenced.
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 alltimes by acompetent 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 thecylinder, 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.
R. 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.
S. 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 appropriate refrigerant recovery cylinders are employed. Ensure that the correct number of cylinders
for holding the total system charge is 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.