High
FAIL POINT H on Worcester Bosch Greenstar 25Si

Your boiler is failing to light the flame, which means it has stopped working to keep you safe.

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: Gas supply issue, spark electrode/HT lead fault, gas valve harness/solenoid resistance fault, or flame sensor/white wire continuity 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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