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REQUIREMENTS FOR OPERATION
Requirements for Operation, Service and Installation of Appliances Using
Flammable Refrigerants
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.
– The following leak detection methods are deemed acceptable for all refrigerant systems.
• Electronic leak detectors may be used to detect refrigerant leaks but, in the case of FLAMMABLE
REFRIGERANTS, 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.
NOTE: Examples of leak detection fluids are:
- bubble method,
- fluorescent method agents.
– 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. Removal of
refrigerant shall be according to the manual.
Removal and evacuation
– When breaking into the refrigerant circuit to make repairs – or for any other purpose – conventional procedures
shall be used. However, for flammable refrigerants it is important that best practice be followed, since
flammability is a consideration. The following procedure shall be adhered to:
a) safely remove refrigerant following local and national regulations;
b) purge the circuit with inert gas;
c) open the circuit by cutting or brazing.
– The refrigerant charge shall be recovered into the correct recovery cylinders if venting is not allowed by
local and national codes. For appliances containing flammable refrigerants, the system shall be purged with
oxygen-free nitrogen to render the appliance safe for flammable refrigerants. This process might need to be
repeated several times.
– Compressed air or oxygen shall not be used for purging refrigerant systems.
Charging procedures
– In addition to conventional charging procedures, the following requirements shall be followed.
– Ensure that contamination of different refrigerants does not occur when using charging equipment. Hoses or
lines shall be as short as possible to minimise the amount of refrigerant contained in them.
– Cylinders shall be kept in an appropriate position according to the instructions.
– Ensure that the REFRIGERATING SYSTEM is earthed prior to charging the system with refrigerant.
– Label the system when charging is complete (if not already).
– Extreme care shall be taken not to overfill the REFRIGERATING SYSTEM.
– Prior to recharging the system, it shall be pressure-tested with the appropriate purging gas. The system shall
be leak-tested on completion of charging but prior to commissioning. A follow up leak test shall be carried out
prior to leaving the site.
31-5001074 Rev. 0
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