Low
004E on Navien NCB300

Your boiler has temporarily sensed a flame when it shouldn't be there, but it has safely cleared itself so your heating should still be working normally.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

False-flame error (automatically cleared)

From this model's manual
Verified against the Navien/Navien Ncb300 Combi Service Manual30k 250328 Pdf installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

003EView →005EView →

All 56 fault codes on the NCB300

Seeing a different code? Every code this model can display, in one place.

001003004012012E016016E030030E031046047109109E205302407515517593594615740782E001E003E004E012E016E030E031E046E047E109E110E205E218E302E351E352E353E407E421E439E515E517E593E594E598E615E740E782E783E787E788

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