Elon 117014, Инструкции по применению

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flammable atmosphere. The test apparatus must have the correct rating.
Only replace components with parts specified by the manufacturer. Any
other parts may result in the ignition of refrigerant in the atmosphere
from a leak.
• Cabling
Check that cabling will not be subject to wear, corrosion, excessive
pressure, vibration, sharp edges or any other adverse environmental
effects. These checks must also take into account the effects of ageing or
continual vibration from sources such as compressors or fans.
• Detection of flammable refrigerants
Under no circumstances may potential sources of ignition be used when
searching or detecting for refrigerant leaks. A halide torch (or any other
detector using a naked flame) must not be used.
• Leak detection methods
The following leak detection methods are deemed acceptable for
systems containing flammable refrigerants. Electronic leak detectors
may be used to detect flammable refrigerants, but the sensitivity may
not be adequate, or may need re-calibration. (Detection equipment must
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 must be set at a percentage of the LFL of the
refrigerant and must be calibrated for the refrigerant employed and the
appropriate percentage of gas (25% maximum) must be confirmed. Leak
detection fluids are suitable for use with most refrigerants but the use
of detergents containing chlorine must be avoided as the chlorine may
react with the refrigerant and corrode the copper pipe-work. If a leak is
suspected, all naked flames must be removed/extinguished. If a leakage
of refrigerant is found which requires brazing, all the refrigerant must 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)
must then be purged through the system both before and during the
brazing process.
• Removal and evacuation
When breaking into the refrigerant circuit to make repairs or for any
other purpose, conventional procedures must be used. However, it is
important that best practice is followed since flammability is a
consideration. The following procedure must 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 must be recovered into the correct recovery
cylinders. The system must be flushed with OFN to render the unit safe.
This process may need to be repeated several times. Compressed air or
oxygen must not be used for this task.
Flushing must be achieved by breaking the vacuum in the system with
OFN and continuing to fill until the working pressure is achieved, then