Low
C4 273 on Worcester Bosch 26 CDi Xtra

Your boiler has detected a small airflow issue while running its daily safety self-test, often meaning it needs a professional service or a minor part cleaned.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

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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