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8
CHARGING PROCEDURES
In addition to conventional charging procedures, the following requirements shall be followed. Ensure that
contamination of different refrigerants does not occur when using charging equipment. Hoses or lines shall be
as short as possible to minimise the amount of refrigerant contained in them. Cylinders shall be kept upright.
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.
9
DECOMMISSIONING
Before carrying out this procedure, it is essential that the technician is completely
familiar with the equipment and all its detail. lt is recommended good practice that all refrigerants are reco-
vered 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. lt is essential that 4 GB electrical power is available before the task is commenced.
a) Become familiar with the equipment and its operation.
b) lsolate system electrically.
c) Before attempting the procedure ensure that: mechanical handling equipment is available, if required, for
handling refrigerant cylinders;
d) All personal protective equipment is available and being used correctly; the recovery process is supervised at
all times by a competent person;
e) recovery equipment and cylinders conform to the appropriate standards.
f) Pump down refrigerant system, if possible.
g) lf a vacuum is not possible, make a manifold so that refrigerant can be removed from various parts of the
system.
h) Make sure that cylinder is situated on the scales before recovery takes place.
i) Start the recovery machine and operate in accordance with manufacturer's instructions.
j) Do not overfill cylinders. (No more than 80 % volume liquid charge).
k) Do not exceed the maximum working pressure of the cylinder, even temporarily.
l) 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.
m) 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 flam-
mable refrigerant.
11 RECOVERY
When removing refrigerant from a system, either for servicing or decommissioning, il 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 hol-
ding 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 com-
plete 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 discon-
nect couplings and in good condition. Before using the recovery machine, check that il is in satisfactory wor-
king 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.
lf 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 healing to the compressor
body shall be employed to accelerate this process. When oil is drained from a system, il shall be carried out
safely.
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