High
AIR FLOW DEVICE on Worcester Bosch 24i RSF

Your boiler has detected an issue with the internal fan or the way it clears exhaust gases, so it has shut down to keep you safe.

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

The appliance will enter a lockout condition in the event of an air flow fault. If the controls fail to detect the correct air flow through the appliance the electricity supply to the gas valve will be interrupted.

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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