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Wiring
Check that the wiring shows no signs of wear, corrosion, excessive pressure, vibration, cutting edges or
any other detrimental environmental effect. The check must also take into account the effects of ageing
or continuous vibrations caused by sources such as compressors or fans.
Detection of flammable refrigerant
Under no circumstances must potential ignition sources be used to search for or detect refrigerant leaks. A
halide torch (or any other detector using a naked flame) must not be used.
The following leak detection methods are considered to be acceptable for all cooling systems.
Electronic leak detectors can be used to detect refrigerant leaks; however, in the case of flammable
refrigerants, the sensitivity level may not be suitable or recalibration may be necessary. (The detection
equipment must be calibrated in an area devoid of refrigerant). Check that the detector is not a
potential ignition source and is appropriate for the refrigerant used. The leak detection equipment must
be adjusted to a percentage of the refrigerant's LFL and must be calibrated according to the refrigerant
used. The appropriate gas percentage (25% at most) must be confirmed.
Leak detection fluids are also suited for use with most refrigerants, however the use of detergents
containing chlorine must be avoided since it could react with the refrigerant and cause corrosion to the
copper piping.
If a leak is suspected, all naked flames must be removed/extinguished.
If a refrigerant leak is detected and requires soldering, the entire quantity of refrigerant must be removed
from the system or isolated (by way of shut-off valves) in part of the system located away from the leak.
Removal and discharge
When accessing the cooling circuit to carry out repairs, or for any other reason, conventional procedures
must be employed. However, for flammable refrigerants, the recommendations must be complied with
in order to take account of the product's flammability. The following procedure must be followed:
remove the refrigerant;
purge the circuit with an inert gas (optional for A2L);
drain (optional for A2L);
purge with an inert gas (optional for A2L);
open the circuit by cutting or soldering.
The refrigerant charge must be recovered in suitable recovery cylinders. For appliances containing
flammable refrigerants other than A2L refrigerants, the system must be bled with nitrogen devoid of
oxygen to make the appliance suitable for receiving flammable refrigerants. You may need to repeat this
process several times. Compressed air or oxygen must not be used to purge cooling systems.
Loading procedures
Check that the vacuum pump outlet is not located in the vicinity of any potential ignition source and that
ventilation is provided.
In addition to conventional charging procedures, the following requirements apply.
Check that there is no possibility of cross-contamination between the different refrigerants when using
charging equipment. Hoses or lines must be as short as possible to reduce the quantity of refrigerant
contained therein.
Cylinders must be kept in an appropriate position, in accordance with the instructions.
Check that the cooling system is grounded before charging the system with refrigerant.
Label the system once charging is complete (if this is not already the case).
Pay close attention to not overfilling the cooling system.
Before recharging the system, carry out a pressure test using a suitable purge gas. The system must be
examined to make sure there are no leaks after the charging operation and before commissioning. A
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