Navien NCB-24LSWE, Service Manual

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84 NCB Service Manual Version 1.0
5.2.2 Error 003
Error Conditions and Checklist
Error Description
E003
Ignition fault
When ignition faults occur, the boiler will attempt ignition 5 times. If a flame does not start, the
system displays ‘003E’ on the front panel. This error code can be cleared manually.
Checklist
1. Check the gas supply valve is open and use a manometer to verify the supply pressure is
correct.
2. Check the ignition gap, spark intensity, and flame rod deformation.
3. Check the operation of the ignition transformer (ignition state, input power (AC 230 V)
4. Check the operation of the gas control valve (DC 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 obstructed.
7. Check if the air pressure sensor is operating correctly.
8. Check the PCB DIP switch settings.
9. Adjust the offset pressure (refer to page 21).
10. Check that the gas orifice used is for the correct gas type.
11. Check the flue and air intake for accumulated water (for vertical flue installations).
12. Tighten the ground connection screws on the heat exchanger.
13. If the error conditions remain after checking these items, replace the PCB.
Scenario1
Check the gas valve assembly