High Lockout
NEON6 on Glow-worm Micron 40FF

Your boiler is failing to light or stay lit, meaning it cannot heat your home or water.

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

FLAME FAILURE

What causes this fault?

This fault occurs when the boiler attempts to start up but cannot detect a stable flame after several attempts. The most common reasons are a worn ignition electrode that can no longer spark correctly, or a faulty gas valve that isn't allowing fuel into the burner.

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

NEON 1View →NEON 3View →

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