Navien NP-180 Service Manual page 70

Scenario 1
Is the igniter normally
operating?
Yes
Check the gas valve assembly
Scenario 2
Is the flame detection
device normally
operating?
Yes
Try to restart
©Navien America Inc. 2010
Does the igniter have proper
No
voltage?
Yes
Is the igniter
electrode clean?
Is the igniter electrode
damaged?
Yes
Replace igniter assembly
Is the flame current
No
detected?
Yes
Replace PCB
68
NR/NP series service Manual
No Replace PCB
Check the voltage between two wires of CN 17:
Same as supply voltage (97 -138 VAC)
No Clean or replace igniter electrode
Remove the burner cover plate and check the
igniter electrode.
Clean or replace the flame rod
Check whether ground circuit is
No
properly installed.
Check the current of CN 19: 7 -20μA
Check the voltage between two wires of CN 19:
10 -20VDC
Version 2.0