Emergency Lockout
F7 on Worcester Bosch Greenstar 25HE

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

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Flame detected even though appliance is switched off

What causes this fault?

This fault occurs when the boiler's internal sensors continue to detect a flame signal even after the gas supply has been shut off. The most common reason is a contaminated flame electrode sending a false signal, or a fault within the main control board that is misinterpreting electrical noise as a live flame.

Engineer required

This is a emergency 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

EAView →E9View →FDView →

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