High Lockout
F7 on Worcester Bosch Greenstar Ri

Your boiler thinks it can still see a flame inside after it has been told to turn off, which is a safety conflict.

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 detected even though boiler switched off.

What causes this fault?

This fault occurs when the boiler's internal sensor continues to detect a flame signal even after the gas valve has been closed. The most common reason is a sensor that has become contaminated or damaged, or a electrical fault in the control board that incorrectly interprets background electrical 'noise' as a live flame.

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

FDView →EAView →C6View →

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