Emergency
A15 on Ferroli Extrema C

Your boiler has detected that the exhaust gases are not venting safely and has shut down to prevent the release of harmful fumes into your home.

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

Air pressure switch (fails to close contacts within 20 sec. of fan activation) due to activation of the fume thermostat

From this model's manual
Verified against the Ferroli Extrema C 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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