Navien NPE-180A, Руководство по обслуживанию

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Troubleshooting 87
Fault
Possible
Causes
Check method
Tightness of Screw or
Ground Bolt
Check the tightness of the screw or ground bolt in the C SC heat exchanger.
-
Cause: Screw or ground bolt in the chamber and SC heat exchanger can be
loosened by the vibration or external impact when operating the boiler (water
heater).
-
Check-up: A failure in the current flow between the chamber and burner may cause
the flame-out; therefore, the tightness (fastened) of the screw needs to be checked.
[Fasten the ground screw (2EA) after fastening the assembly screw (3EA) in the front
of the heat exchanger]
[Location of assembly screw and ground bolt in heat exchanger]
Defected metal fiber
1 Check the presence of debris in the metal fiber.
2 Check the sagging of the metal fiber and then the gaps with the electrode.
[Gap between the electrode and metal fiber: 12mm]
Flame loss during 2nd
stage
Blockage
in the gas
orifice plate.
Flame loss will occur if the gas orifices are clogged.
●
Remove the gas inlet pipe and check for debris; remove and clean the orifice plate if necessary.
Other trouble
Defective
PCB
If the issue continues despite checking above items, replace the PCB.