Costway FP10275DE Bedienungsanleitung Seite 18

Leak detection fluids are suitable for use with most refrigerants but
the use of detergents containing chlorine shall be avoided as
the chlorine may react with the refrigerant and corrode the copper
pipe-work.
If a leak is suspected, all naked flames shall be removed/
extinguished.
If a leakage of refrigerant is found which requires brazing, all of
the refrigerant shall be recovered from the system, or isolated (by
means of shut off valves) in a part of the system remote from the leak.
Oxygen free nitrogen (OFN) shall then be purged through
the system both before and during the brazing process.
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.
1)
Purge the circuit with inert gas.
2)
3)Evacuate.
Purge again with inert gas.
4)
Open the circuit by cutting or brazing.
5)
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.
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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.
8. 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.
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