Midea MAW User Manual page 10

13. Decommissioning.
Before carrying out this procedure, it is essential that the technician is completely familiar with the
unit and all its detail. It is recommended good practice that all refrigerants are recovered safely.
Before commencing the task, it is essential to take oil and refrigerant samples in case analysis is needed
before reclaimed refrigerant can be reused. Ensure electrical power is available prior to starting the task.
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. If possible, pump down the refrigerant system.
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 instructions.
h. Do not overfi ll 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 fi lled 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.
14. Labeling.
Equipment shall be labeled 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 unit stating the unit contains flammable refrigerant.
15. 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 labeled 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 unit shall be in good working order with a set of instructions concerning the unit that is at
hand and shall be suitable for the recovery of the flammable refrigerant. If in doubt, the manufacturer
should be consulted. 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.
The recovered refrigerant shall be processed according to local legislation 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 fl ammable refrigerant does not remain within the lubricant. The
compressor body shall not be heated by an open fl ame or other ignition sources to accelerate this process.
When oil is drained from a system, it shall be carried out safely.
Non-duct connected appliances containing A2L refrigerants with the supply and return air openings in the
conditioned space may have the body of the appliance installed in open areas such as false ceilings not
being used as return air plenums, as long as the conditioned air does not directly communicate with the air
of the false ceiling.
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