Emergency
E03 on Baxi Duo-tec Combi

Your boiler has detected an issue with the ventilation system that clears away exhaust gases, so it has safely shut down to prevent any risk.

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 thermostat / flue pressure switch trip

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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