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SAFETY OPERATION OF FLAMMABLE REFRIGERANT
is commenced.
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.
14. Decommissioning
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
using charging equipment. Hoses or lines shall be as short as possible to minimise
followed. Ensure that contamination of different refrigerants does not occur when
In addition to conventional charging procedures, the following requirements shall be
Charging procedures13.
there is ventilation available.
Ensure that the outlet for the vacuum pump is not close to any ignition sources and
operation is absolutely vital if brazing operations on the pipe-work are to take place.
shall be vented down to atmospheric pressure to enable work to take place.
This
refrigerant is within the system. When the final OFN charge is used, the system
and finally pulling down to a vacuum. This process hall be repeated until no
continuing to fill until the working pressure is achieved, then venting to atmosphere,
Flushing shall be achieved by breaking the vacuum in the system with OFN and
be repeated several times. Compressed air oxygen shall not be used for this task.
system shall be flushed with OFN to render the unit safe. This process may need to
The refrigerant charge shall be recovered into the correct recovery cylinders.
The
•
Open the circuit by cutting or brazing.
•
Purge again with inert gas;
•
Evacuate;
•
Purge the circuit with inert gas;
•
Remove the refrigerant;
adhered to:
followed since flammability is a consideration. The following procedure shall be
conventional procedures shall be used. However, it is important that best practice is
When breaking into the refrigerant circuit to make repairs or for any other purpose
Removal and evacuation12.
process.
shall then be purged through the system both before and during the brazing
values) in a part of the system remote from the leak. Oxygen free nitrogen (OFN)
refrigerant shall be recovered from the system, or isolated (by means of shut off
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