Emergency Lockout
FA on Worcester Bosch Greenstar Ri

Your boiler thinks a flame is still present even though the gas should have been turned off, which is a safety concern that prevents it from running.

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 after gas shut off.

What causes this fault?

This fault occurs when the boiler's internal sensor continues to detect a flame even after the system has commanded the gas supply to close. The most common reason is a gas valve that is physically stuck open or leaking, though it can also be caused by a sensing electrode or control board incorrectly reporting fire when none exists.

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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