High Lockout
228 on Worcester Bosch Greenstar 8000 Life/Style

Your boiler thinks a flame is burning even though it hasn't actually sparked or started, causing it to shut 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

Flame signal without flame present

What causes this fault?

This fault occurs when the boiler's internal sensors mistakenly detect a flame signal while the burner should be off. The most common reason is a faulty or contaminated sensing electrode that is sending a false electrical signal to the control board, preventing the boiler from starting for safety reasons.

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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Related fault codes

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