Bauknecht SPIW312A3BK Gebrauchsanweisung Seite 25

SAFETY INSTRUCTIONS
9. Cabling
Check that cabling will not be subject to wear, corrosion, excessive pressure, vibration, sharp
edges or any other adverse environmental effects.The check shall also take into account the
effects of aging or continual vibration from sources such as compressors or fans.
10.Detection of flammable refrigerants
Under no circumstances shall potential sources of ignition be used in the searching for or
detection of refrigerant leaks. A halide torch (or any other detector using a naked flame)
shall not be used.
11.Leak detection methods
The following leak detection methods are deemed acceptable for systems containing
flammable refrigerants:
- Electronic leak detectors shall be used to detect flammable refrigerants, but the
sensitivity may not be adequate, or may need re-calibration (Detection equipment shall
be calibrated in a refrigerant-free area.)
- Ensure that the detector is not a potential source of ignition and is suitable for the
refrigerant used.
- Leak detection equipment shall be set at a percentage of the LFL of the refrigerant and
shall be calibrated to the refrigerant employed and the appropriate percentage of gas
(25% maximum) is confirmed.
- 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.
12.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 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 charge is used, the system shall be vented
down to atmospheric pressure to enable work. This operation is absolutely vital if brazing
operations, on the pipe-work are to take place. Ensure that the outlet for the vacuum
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