Pro-Elec PELL0374 - Charging Procedures; Decommissioning

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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 ll until the working pressure is achieved, then venting to
atmosphere, and nally pulling down to a vacuum. This process shall be repeated
until no refrigerant is within the system. When the nal 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.
Charging procedures
• In addition to conventional charging procedures, the following requirements shall
be followed.
1. Ensure that contamination of di󰀨erent 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.
2. Cylinders shall be kept upright.
3. Ensure that the refrigeration system is earthed prior to charging the system
with refrigerant.
4. Label the system when charging is complete (if not already).
5. Extreme care shall be taken not to overll the refrigeration system.
6. Prior to recharging the system it shall be pressure tested with OFN.
7. 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.
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 is commenced.
• Become familiar with the equipment and its operation.
• Isolate system electrically.
• Before attempting the procedure ensure that:
1. Mechanical handling equipment is available, if required, for handling
refrigerant cylinders.
2. All personal protective equipment is available and being used correctly.
3. Pump down refrigerant system, if possible.
4. If a vacuum is not possible, make a manifold so that refrigerant can be
removed from various parts of the system.
5. Make sure that cylinder is situated on the scales before recovery takes place.
6. Start the recovery machine and operate in accordance with manufacturer’s
instructions.
7. Do not overll cylinders. (No more than 80% volume liquid charge).