Charging Procedures - Qlima MS-AC 5002 Operating Manual

since flammability is a consideration. The following procedure shall be adhered to: remove
refrigerant; purge the circuit with inert gas; evacuate; purge again with inert gas; open the
circuit by cutting or brazing.The refrigerant charge shall be recovered into the correct recovery
cylinders. The system shall be "flushed" with OFN to render the unit safe. This process may need
to be repeated several times. Compressed air or oxygen shall not be used for this task. Flushing
shall be achieved by breaking the vacuum in the system with OFN and continuing to fill until the
working pressure is achieved, then venting to atmosphere, and finally pulling down to a vacuum.
This process shall be repeated until no refrigerant is within the system.
When the final OFN charge is used, the system shall be vented down to atmospheric pressure to
enable work to take place. This operation is absolutely vital if brazing operations on the pipework
are to take place. Ensure that the outlet tor the vacuum pump is not close to any ignition sources
and !here is ventilation available.
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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 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. 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 flammable 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 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
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