High
Ignition failure on Navien NCB 28 HE

Your boiler is failing to light the internal flame, which means it cannot produce any hot water or heating for your home.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Gas supply fault, Electrode gap and shape faults, No spark from the electrode, Ignition transformer, or Main gas valve failure.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E001View →E003View →

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