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SAFETY INSTRUCTIONS
Do not apply any permanent inductive or capacitance loads to the circuit without ensuring
that this will not exceed the permissible voltage and current permitted for the equipment
in use. Intrinsically safe components are the only types that can be worked on whilelive in
the presence of a flammable atmosphere. The test apparatus shall be at the correct rating.
Replace components onlywith parts specified by the manufacturer. Other parts may result
in the ignition of refrigerant 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.
10. 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 also 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.
11. 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 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 purged with OFN to render the appliance safe for flammable refrigerants. This
process may need to be repeated several times. Compressed air or oxygen shall not be
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