Mitsubishi Electric s-AIRME-G02 Instructions For Installation, Use And Maintenance Manual page 17

This damper keeps the unit in communication with the outside environment, ensuring the evacuation of any refrigerant
leakage.
For further information refer to the dedicated chapter 4.6.
MAINTENANCE
The following precautions must be taken before working on the refrigerant circuit:
•
Obtain a permit for work on hot parts (if required);
•
Ensure that no flammable materials are stored in the work area and that no ignition sources are present anywhere in the
work area;
•
Ensure that suitable fire extinguishing equipment (CO2 or dry-powder type) is available within the immediate area;
•
Ensure that the work area is properly ventilated before working on the refrigerant circuit or before welding, brazing or
soldering work. Use auxiliary ventilation, rated for R32 refrigerant, such as blowers or fans, if necessary, to disperse
refrigerant vapours, especially in confined areas. (This recommendation applies, in any case, to all refrigerants);
•
Ensure that suitable flammable gas detectors are present and operating to warn workers of a dangerous concentration of
refrigerants, especially during any work on hot parts;
•
Ensure that the leak detection equipment being used is non-sparking, adequately sealed or intrinsically safe;
• Display appropriate warning signs. For example, "no smoking" and "no entry";
•
Verify that all appropriate and necessary tools and Personal Protective Equipment (PPE) are available;
•
Ensure that all maintenance staff have been instructed.
NOTE: When installation permits, it is recommended to remove the equipment from the existing position to a controlled
workshop environment where work can be carried out safely.
The following procedure must be followed before working on the refrigerant circuit:
•
Remove the refrigerant (specify the residual pressure);
•
Purge the circuit with inert gas (e.g. nitrogen);
•
Evacuate at a pressure of 30 kPa absolute (or 0.03 MPa);
•
Purge again with inert gas (e.g. nitrogen);
•
Open the circuit.
•
Do not braze pipe and components which contain refrigerant. Before opening the circuit, the refrigerant must be recovered
or pumped down. To open the pipelines, use only pipe cutters. Do not use naked flames. Before brazing, check with a
refrigerant detector the absence of a potential flammable atmosphere. Refrain from using flames until the work environment
is adequately ventilated.
•
If compressors or compressor oils are to be removed, evacuate to an acceptable level to ensure that there is no flammable
refrigerant remaining within the lubricant.
•
Only refrigerant recovery equipment designed for use with flammable refrigerants must be employed. HFC refrigerant
recovery machines may not have been assessed for use with flammable refrigerants. If the national rules or regulations
permit the refrigerant to be drained, this should be done safely, using a hose, for example, to discharge the refrigerant into
the outside atmosphere in a safe area. It should be ensured that an inflammable explosive refrigerant concentration cannot
occur near an ignition source or penetrate into a building under any circumstance.
•
After any repair work, the safety devices, e.g. refrigerant detectors and mechanical ventilation systems, shall be checked
and the results recorded.
•
It shall be ensured that any missing or illegible labels on components of the refrigerant circuit are replaced.
•
Sources of ignition shall not be used when searching for a refrigerant leak.
•
Maintenance and repair requiring the assistance of other skilled personnel shall be carried out under the supervision of the
person competent in the use of flammable refrigerants. Any person conducting servicing or maintenance on a system or
associated parts of the equipment shall be competent according to EN 13313.
Installation, use and maintenance manual 17