Panasonic Inverter R32 Series Technical Data & Service Manual page 182

(8) Repair and maintenance to electrical components shall include initial safety checks and component inspection procedures. If a fault
exists that could compromise safety, then no electrical supply shall be connected to the circuit until it is satisfactorily dealt with. If
the fault cannot be corrected immediately but it is necessary to continue operation, an adequate temporary solution shall be used.
This shall be reported to the owner of the equipment so all parties are advised.
Initial safety checks shall include:
•
That no live electrical components and wiring are exposed while charging, recovering or purging the system.
•
That there is continuity of earth bonding.
During repairs to sealed components, all electrical supplies shall be disconnected from the equipment being worked upon prior to
any removal of sealed covers, etc.
Particular attention shall be paid to the following to ensure that by working on electrical components, the casing is not altered in
such a way that the level of protection is affected. This shall include damage to cables, excessive number of connections, terminals
not made to original specifi cation, damage to seals, incorrect fi tting of glands, etc.
Ensure that apparatus is mounted securely.
Ensure that seals or sealing materials have not degraded such that they no longer serve the purpose of preventing the ingress of
fl ammable atmospheres.
Replacement parts shall be in accordance with the manufacturer's specifi cations.
NOTE:
The use of silicon sealant may inhibit the effectiveness of some types of leak detection equipment. Intrinsically safe components do
not have to be isolated prior to working on them.
Do not apply any permanent inductive or capacitance loads to the circuit without ensuring that this will not exceed the permissible
voltage and current permitted for the equipment in use.
Intrinsically safe components are the only types that can be worked on while live in the presence of a fl ammable atmosphere.
The test apparatus shall be at the correct rating.
Replace components only with parts specifi ed by the manufacturer. Unspecifi ed parts by manufacturer may result ignition of
refrigerant in the atmosphere from a leak.
REMOVAL AND EVACUATION
CAUTION
When breaking into the refrigerant circuit to make repairs – or for any other purpose – conventional procedures shall be used.
However, it is important that best practice is followed since fl ammability is a consideration.
The following procedure shall be adhered to:
•
Remove refrigerant.
•
Purge the circuit with inert gas.
•
Evacuate.
•
Purge again with inert gas.
•
Open the circuit by cutting or brazing.
The refrigerant charge shall be recovered into the correct recovery cylinders.
The system shall be "fl ushed" with Oxygen free nitrogen (OFN) to render the unit safe.
This process may need to be repeated several times.
Compressed air or oxygen shall not be used for this task.
Flushing shall be achieved by breaking the vacuum in the system with Oxygen free nitrogen (OFN) and continuing to fi ll until the
working pressure is achieved, then venting to atmosphere, and fi nally pulling down to a vacuum.
This process shall be repeated until no refrigerant is within the system.
When the fi nal Oxygen free nitrogen (OFN) charge is used, the system shall be vented down to atmospheric pressure to enable
work to take place.
This operation is absolutely vital if brazing operations on the pipe work are to take place.
Ensure that the outlet for the vacuum pump is not close to any ignition sources and there is ventilation available.
CHARGING PROCEDURES
NOTE
NOTE
■
See " Outdoor Unit" under the Section 1-11. Installation Instructions.
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