High
Lock-out on Worcester Bosch Worcester 25/30 HE

Your boiler has stopped working because it failed to light or stay lit, causing it to shut down for safety reasons.

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.

What the manual says

Manufacturer manual

The burner will go out but sparking from the electrode will continue for 10 seconds. This can occur if the gas supply is turned off during operation.

From this model's manual
Verified against the Worcester Bosch Worcester 25 30 He installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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