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4.0 Removal and Evacuation
When breaking into the refrigerant circuit to make repairs – or for any other purpose – conventional procedures shall
be used. However, for 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 (optional for A2L);
• evacuate (optional for A2L);
• purge with inert gas (optional for A2L);
• open the circuit by cutting or brazing.
The refrigerant charge shall be recovered into the correct recovery cylinders. For appliances containing Flammable
refrigerant other than A2L Refrigerants, the system shall be purged with oxygen-free nitrogen to render the appliance
safe for Flammable refrigerant. This process may need to be repeated several times. Compressed air or oxygen shall
not be used for purging refrigerant systems.
5.0 Recovery
When removing refrigerant from a system, either for servicing or decommissioning, it is recommended good practice
that all refrigerants are removed safely.
When transferring refrigerant into cylinders, ensure that only appropriate refrigerant recovery cylinders are employed.
Ensure that the correct number of cylinders for holding the total system charge is available. All cylinders to be used
are designated for the recovered refrigerant and labelled for that refrigerant (i.e. special cylinders for the recovery of
refrigerant). Cylinders shall be complete with pressure-relief valve and associated shut-off valves in good working
order. Empty recovery cylinders are evacuated and, if possible, cooled before recovery occurs.
The recovery equipment shall be in good working order with a set of instructions concerning the equipment that is
at hand and shall be suitable for the recovery of all appropriate refrigerants including, when applicable, flammable
refrigerants. In addition, a set of calibrated weighing scales shall be available and in good working order. Hoses shall
be complete with leak-free disconnect couplings and in good condition. Before using the recovery machine, check
that it is in satisfactory working order, has been properly maintained and that any associated electrical components
are sealed to prevent ignition in the event of a refrigerant release. Consult manufacturer if in doubt.
The recovered refrigerant shall be returned to the refrigerant supplier in the correct recovery cylinder, and the relevant
waste transfer note arranged. Do not mix refrigerants in recovery units and especially not in cylinders.
If compressors or compressor oils are to be removed, ensure that they have been evacuated to an acceptable level
to make certain that flammable refrigerant does not remain within the lubricant. The evacuation process shall be
carried out prior to returning the compressor to the suppliers. Only electric heating to the compressor body shall be
employed to accelerate this process. When oil is drained from a system, it shall be carried out safely.
