Navien NFC-175, Service Manual

Page: 77 / 138

NFC Service Manual 77 Version 1.0
Failure mode Cause Check method
Ignition failure
Igniter
Flame Rod
Ignite gap distance : 3.5~4.5mm (1/8”)
No spark from electrode
When no spark is made from the electrode at ignition:
●
Remove the electrode and check if there is a crack on the insulator.
●
Adjust the gap if there is a discharge of electricity from the metallic part of the burner.
●
Ensure that the insulating gasket is installed between the electrode and burner casing.
●
Check the input power to the ignition transformer (AC 96 ~ 138 V).
●
If there is sufficient power to the ignition transformer, replace the ignition transformer.
●
Replace the PCB if there is no power or insufficient power supplied to the ignition
transformer.
●
Check the insulator boots on the spark wires for cracks / holes.
Ignition transformer