Emergency Lockout
8.F on Worcester Bosch Greenstar CDi Compact

Your boiler has detected a flame when there shouldn't be one, which usually means a internal component is stuck or damaged.

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

Permanent ignition

What causes this fault?

This fault occurs when the boiler's sensors detect a flame still burning even after the heating or hot water has been turned off. The most common reason is an internal component like the gas valve becoming stuck open or an electrical failure on the main control board that keeps the ignition system active. Because this involves gas flow that isn't being controlled properly, the boiler shuts down immediately as a safety precaution.

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 →C6View →F7View →

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