High
227 on Worcester Bosch Greenstar 4000

Your boiler is trying to start but the flame is failing to light or stay lit, so it has safely shut itself down to prevent a gas build-up.

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

No flame signal after ignition

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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