9
SAFETY INSTRUCTIONS
– 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.
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 pipe-work are to take place. Ensure that the outlet for the vacuum
pump is not close to any ignition sources and there is ventilation available.
In addition to conventional charging procedures, the following requirements shall be followed.
Charging procedures
Before carrying out this procedure, it is essential that the technician is completely familiar with the equipment
and all its detail.
It 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. It is essential that electrical power is available before the task is
commenced.
a) Become familiar with the equipment and its operation.
b) Isolate system electrically.
d) Pump down refrigerant system, if possible.
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 80 % volume liquid charge).
i ) Do not exceed the maximum working pressure of the cylinder, even temporarily.
k) Recovered refrigerant shall not be charged into another refrigeration system unless it has been cleaned
and checked.
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.
e) If a vacuum is not possible, make a manifold so that refrigerant can be removed from various parts of
the system.
c) Before attempting the procedure ensure that:
Decommissioning
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.
Labelling
EN
Summary of Contents for W121CE SL0
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