High
228 on Worcester Bosch 1000

Your boiler has detected a sensor error where it believes a flame is present when it isn't, and it has safely locked itself out to prevent any issues.

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?

False flame detection

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

227View →229View →

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