d)Pump down refrigerant system, if possible.
e) If a vacuum is not possible, make a manifold so that refrigerant can be remo-
ved 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 70% liquid volume. The liquid density
of the refrigerant with a reference temperature of 50°C).
i) Do not exceed the maximum working pressure of the cylinder, even tempo-
rarily.
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.
18. 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.
19. Recovery
When removing refrigerant from a system, either for service or decommis-
sioning, 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 numbers
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 retruning 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.
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