High
LOCKOUT on Worcester Bosch Greenstar 25Si

Your boiler has failed to light the flame several times and has shut down completely to prevent gas from escaping.

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

Wait 65 seconds, 5th attempt? Stop spark. Stop pump. Stop fan.

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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