Navien NCB-180, Service Manual

Page: 83 / 149

80 NCB Service Manual Version 1.0
5.2.1 003Error
Error occurrence conditions and check items
Error Description
E003
Ignition failure
In the case of an ignition failure, the boiler will attempt ignition 10 times. If no flame is detected, the
system displays the error message 003E (manually cleared) on the Front Panel.
Check items
1. Check if the gas supply valve is open and for proper supply pressure.
2. Check the electrode gap, electricity discharge, or deformation of the flame rod.
3. Check the operation of the ignition transformer (ignition state, input power (AC 102~132 V)
4. Check the operation of the gas control valve (DC 22~24 V, coil short circuit, solenoid valve).
5. Check the flame rod, wiring and grounding.
6. Check if the air pressure hose is broken or clogged.
7. Check if the air pressure sensor works properly.
8. Check the PCB DIP switch settings.
9. Adjust the offset pressure (see page 30).
10. Check the gas orifice plate for the proper gas type.
11. Check the flue and air supply for any collected water (for vertical vent installations).
12. Tighten the ground connection screws on heat exchanger.
13. If the issues continue despite checking the items above, replace the PCB.
Scenario1
Does the igniter have
proper voltage?
NO
Is the igniter
operating normally?
NO
Check the voltage between #1 and #2 of CN17:
Same as supply voltage (97 – 138 VAC)
(see page 56 for Wiring Diagram)
Check connector
Clean or replace igniter
electrode
NO
Yes
Is the igniter
electrode clean?
Is the igniter electrode
damaged?
Yes
Yes
Replace igniter assembly
Check the gas valve assembly