Medium
274 on Worcester Bosch Greenstar 12i System

Your boiler has detected that it is still sensing a flame even when it should be turned off, which can indicate a small internal electrical or sensor issue.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Ionisation signal present during last 24 hours

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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