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16. Charging procedures
In addition to conventional charging procedures, the following requirements shall be followed:
Works shall be undertaken with appropriate tools only (In case of uncertainty, please consult
the manufacturer of the tools for use with flammable refrigerants)
Ensure that contamination of different refrigerants does not occur when using charging
equipment. Hoses or lines shall be as short as possible to minimize 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. For appliances
containing FLAMMBLE REFRIGERNATS, 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 puring refrigerant systems.
For appliances containing FLAMMABLE REFRIGERNATS, 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 closed to any ignition sources and there
is ventilation available.
17. 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 or safely vented(For R290 refrigerant models). 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
c) Before attempting the procedure ensure that:
mechanical handling equipment is available, if required, for handling refrigerant cylinders;
all personal protetive 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.
