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.

What the manual says

Manufacturer manual

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.

From this model's manual
Verified against the Worcester Bosch 24i Rsf installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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