Safety precautions
live in the presence of a flammable atmosphere. The test apparatus shall be at
the correct rating.
Replace components only with parts specified by the manufacturer.
Other parts may result in the ignition of refrigerant in the atmosphere from a
leak.
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;
CAUTION
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