High
lockout on Worcester Bosch 24CDi BF

Your boiler is failing to light the flame, so it has purposefully shut down to prevent gas from escaping into your home.

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

The burner will go out but sparking from the electrode will continue for 10 seconds when the appliance will enter a ‘lockout’ state.

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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