Medium
C4 273 on Worcester Bosch Hideaway

Your boiler has detected that the fan was running or air was moving through the system when it should have been off during its daily safety check.

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

Airflow present during last 24 hour

Engineer required

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

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Related fault codes

C6View →A1View →

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