Emergency
Air flow fault on Worcester Bosch 24si II

Your boiler is failing to clear combustion fumes properly and has automatically shut down to keep your home safe.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

The fault indicator will flash (approximately five times per second). The controls fail to detect the correct air flow and the electricity supply to the gas valve is interrupted.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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