Vostok VOSPAC10KWA, Руководство пользователя

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7
Removal and Evacuation:
When breaking into the refrigerant circuit to make repairs – or for any other purpose –
conventional procedures shall be used. However, it is important that best practice is
followed 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, 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 vital if brazing operations on the
pipework 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 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.
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 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.