Emergency
27 on Alpha 240XE

Your boiler is struggling to clear exhaust gases properly, likely because the ventilation system is blocked or the internal sensor is misreading the airflow.

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

Flue hood

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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