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Competence of service personnel
General
Special training additional to usual refrigerating equipment repair procedures is required when
equipment with flammable refrigerants is affected.
In many countries, this training is carried out by national training organizations that are accredited to
teach the relevant national competency standards that may be set in legislation.
The achieved competence should be documented by a certificate.
Training
The training should include the substance of the following:
Information about the explosion potential of flammable refrigerants to show that flammables may be
dangerous when handled without care.
Information about potential ignition sources, especially those that are not obvious, such as lighters,
light switches, vacuum cleaners, electric heaters.
Information about the different safety concepts:
Unventilated – (see Clause GG.2) Safety of the appliance does not depend on ventilation of the
housing. Switching off the appliance or opening of the housing has no significant effect on the safety.
Nevertheless, it is possible that leaking refrigerant may accumulate inside the enclosure and
flammable atmosphere will be released when the enclosure is opened.
Ventilated enclosure – (see Clause GG.4) Safety of the appliance depends on ventilation of the
housing. Switching off the appliance or opening of the enclosure has a significant effect on the safety.
Care should be taken to ensure a sufficient ventilation before.
Ventilated room – (see Clause GG.5) Safety of the appliance depends on the ventilation of the room.
Switching off the appliance or opening of the housing has no significant effect on the safety. The
ventilation of the room shall not be switched off during repair procedures.
Information about the concept of sealed components and sealed enclosures
according to IEC 60079-15:2010.
Information about the correct working procedures:
1. Commissioning
o
Ensure that the floor area is sufficient for the refrigerant charge or that the ventilation
duct is assembled in a correct manner.
o
Connect the pipes and carry out a leak test before charging with refrigerant.
o
Check safety equipment before putting into service.
2. Maintenance
o
Portable equipment shall be repaired outside or in a workshop specially equipped for
servicing units with flammable refrigerants.
o
Ensure sufficient ventilation at the repair place.
o
Be aware that malfunction of the equipment may be caused by refrigerant loss and a
refrigerant leak is possible.
o
Discharge capacitors in a way that won’t cause any spark. The standard procedure to
short circuit the capacitor terminals usually creates sparks.
o
Reassemble sealed enclosures accurately. If seals are worn, replace them.
o
Check safety equipment before putting into service.
3. Repair
o
Portable equipment shall be repaired outside or in a workshop specially equipped for
servicing units with flammable refrigerants.
o
Ensure sufficient ventilation at the repair place.
o
Be aware that malfunction of the equipment may be caused by refrigerant loss and a
refrigerant leak is possible.
o
Discharge capacitors in a way that won’t cause any spark.
o
When brazing is required, the following procedures shall be carried out in the right
order:
Remove the refrigerant. If the recovery is not required by national regulations, drain
the refrigerant to the outside. Take care that the drained refrigerant will not cause
any danger. In doubt, one person should guard the outlet. Take special care that
drained refrigerant will not float back into the building.
Evacuate the refrigerant circuit.
Purge the refrigerant circuit with nitrogen for 5 min.
