High
LOCKOUT LIGHT FLASHING on Worcester Bosch 24i/28i Junior

Your boiler has stopped working because it failed to light or stay lit, so it has purposefully shut itself down for safety.

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

Burner Lockout. Possible causes: gas supply issue, spark electrode/lead failure, gas valve failure, flame sense electrode/cable failure, or control board fault.

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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