14.
Decommissioning
Before carrying out this procedure, it is essential that the technician is completely familiar with the
equipment and all its specifications. It is a recommended good practice that all refrigerants are
recovered safely. Prior to the task being carried out, an oil and refrigerant sample should be taken
in case an analysis is required prior to the re-use of reclaimed refrigerant. It is essential that
electrical power is available before this task is initiated.
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 the cylinder is situated within the range before recovery takes place. g)
Start the recovery machine and follow the manufacturer's instructions. h) Do not overfill cylinders.
(No more than 80% of 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 should not be charged into
another refrigeration system unless it has been cleaned and checked.
15.
Labelling
The equipment shall bear labels stating that it has been de-commissioned and emptied of
refrigerant. The label should be dated and signed. Ensure that there are labels on the equipment
stating that it contains flammable refrigerant.
16.
Recovery
When transferring refrigerant into cylinders, ensure that only appropriate refrigerant recovery
cylinders are filled. Assure that you have the correct number of cylinders to hold the total available
system charge. All used cylinders should be designated and labelled according to the recovered
refrigerant (i.e. special refrigerant recovery cylinders). Cylinders should be complete with a
pressure relief valve and stop valves in good working order. Empty recovery cylinders are
evacuated and, if possible, cooled before recovery begins. The recovery equipment has to be in a
good working order and with a set of instructions concerning the equipment used and if the
recovery of flammable refrigerants is suitable. In addition, a set of calibrated weighing scales shall
be available and in perfect condition. Hoses shall be complete with leak-free disconnect couplings
and also in a flawless condition. Before using the recovery machine, check that it is working, 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 should be returned to the refrigerant
supplier in the appropriate cylinder, and within the relevant Waste Transfer Note attached. Do not
mix refrigerants in recovery units and especially not in cylinders.
If compressors or compressor oils are removed, ensure that they have been evacuated to an
acceptable level to make sure that the flammable refrigerant does not remain mixed with the
lubricant. The evacuation process shall be carried out prior to returning the compressor to the
suppliers. Only electric heating should be applied to the compressor body to accelerate this
process. Oil should be safely drained from the system.
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