Emergency Lockout
LOCKOUT: d on Potterton Housewarmer

Your boiler has shut down because the exhaust fumes are not being cleared away safely through the chimney or flue.

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

INADEQUATE FLUE DRAUGHT

What causes this fault?

This fault occurs when the boiler's safety sensors detect that harmful exhaust gases are not being pulled out of your home effectively. The most common reasons include a failing internal fan that isn't spinning fast enough, a blocked flue pipe, or a faulty sensor that is incorrectly reporting a lack of airflow.

This issue can occur during periods of high winds, which can create back-pressure in the flue and prevent the boiler from venting correctly.

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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