High
Lock-out on Worcester Bosch 28 RSF

Your boiler is failing to light the flame properly, so it has purposefully shut down to prevent gas from building up inside.

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 'lock-out'. Usually caused by gas supply failure or ignition failure.

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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