cecotec FORCECLIMA 7100 SOUNDLESS Manuel D'instructions page 70

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of refrigerant leaks. Do not use a halide lamp or any other detector using a naked flame.
6. Leak-detection methods
- The following leak-detection methods are considered acceptable for systems containing
flammable refrigerants.
- Electronic leak detectors should be used to detect flammable refrigerants, but the
sensitivity may not be adequate, or may need recalibration (the detection equipment should
be calibrated in a refrigerant-free area). Ensure that the detector is not a potential ignition
source and that it is suitable for the refrigerant used. The leak-detection equipment must
be set to a percentage of the lower flammability limit of the refrigerant and calibrated for
the refrigerant used with the appropriate percentage of gas (maximum 25%) confirmed.
- Leak-detection fluids are suitable for use with most refrigerants, but the use of detergents
containing chlorine must be avoided, as chlorine can react with the refrigerant and corrode
copper pipes.
- If a leak is suspected, all naked flames must be eliminated/extinguished.
- If a refrigerant leak is found and requires brazing, all refrigerant must be recovered from
the system, or isolated (by means of shut-off valves) in a part of the system far away from
the leak. Oxygen-free nitrogen must then be purged through the system both before and
during the brazing process.
7. Removal and evacuation
When intervening in the cooling circuit for repairs or any other purpose, conventional
procedures must be followed. However, it is important that best practices are followed, as
flammability is a matter to be taken seriously. The following procedure is to be followed:
1. Remove the refrigerant.
2. Purge the circuit with inert gas.
3. Evacuate.
4. Purge again with inert gas.
5. Open the circuit by cutting or brazing.
- The refrigerant charge must be recovered from the correct recovery cylinders. The system
must be flushed with oxygen-free nitrogen to render the unit safe. This process may need
to be repeated several times. Oxygen or compressed air must not be used for the task.
- Cleanliness must be achieved by breaking the vacuum in the system with oxygen-
free nitrogen and continuing to fill until working pressure is reached, then venting to
atmosphere, and finally pushing to a vacuum. This process must be repeated until there
is no refrigerant left in the system. When using the oxygen-free nitrogen end-charge,
the system must be vented to atmospheric pressure to allow for work. This operation is
absolutely vital if brazing operations are to take place on pipes.
- Ensure that the vacuum pump outlet is not near any source of ignition and that ventilation
is available.
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FORCECLIMA 7100 SOUNDLESS