High Lockout
E011 on Vokera Evolve

Your boiler has detected a flame when there shouldn't be one, or the sensor incorrectly thinks a fire is lit, causing it to shut down for safety.

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

Extraneous flame

What causes this fault?

This fault occurs when the boiler's control system detects a flame signal at a time when the gas should be turned off. This is often caused by a faulty sensor sending a false signal, a gas valve that is leaking slightly, or a glitch in the main circuit board that misinterprets electrical background noise as a fire.

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

E042View →

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