High Lockout
F14 on Glow-worm Xtramax HE

Your boiler has detected an internal electrical problem with the component that controls the gas supply, meaning it cannot ignite safely for heating or hot 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

Gas valve control fault.

What causes this fault?

This fault occurs when the boiler's main control board loses communication with the gas valve or detects an electrical signature that suggests the valve is unsafe to operate. The most common reason is a component failure within the gas valve itself, though damaged wiring or a fault on the printed circuit board can also prevent the signal from being sent correctly.

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

F1View →F4View →F12View →

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