Emergency
Air Flow Monitor on Potterton Performa 24 Eco HE

Your boiler has detected that it cannot breathe properly, meaning it is unable to safely vent exhaust gases, so it has turned itself off to prevent a safety hazard.

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.

What the manual says

Manufacturer manual

Flue or flue terminal is blocked or obstructed, or an internal fault

From this model's manual
Verified against the Potterton Performa 24 Eco He 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 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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