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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 – 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 – 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 – 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:
a) Commissioning
• Ensure that the floor area is sufficient for the refrigerant charge or that the ventilation hose is assembled in a
correct manner.
• Connect the pipes and carry out a leak test before charging with refrigerant.
• Check safety equipment before putting into service.
b) Maintenance
• Portable equipment shall be repaired outside or in a workshop specially equipped for servicing units with
flammable refrigerants.
• Ensure sufficient ventilation at the repair place.
• Be aware that malfunction of the equipment may be caused by refrigerant loss and a refrigerant leak is
possible.
• Discharge capacitors in a way that won’t cause any spark. The standard procedure to short circuit the
capacitor terminals usually creates sparks.
• Reassemble sealed enclosures accurately. If seals are worn, replace them.
• Check safety equipment before putting into service.
c) Repair
• Portable equipment shall be repaired outside or in a workshop specially equipped for servicing units with
flammable refrigerants.
• Ensure sufficient ventilation at the repair place.
• Be aware that malfunction of the equipment may be caused by refrigerant loss and a refrigerant leak is
possible.
• Discharge capacitors in a way that won’t cause any spark.
• 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.
– Evacuate again.
– Remove parts to be replaced by cutting, not by flame.
– Purge the braze point with nitrogen during the brazing procedure.