Emergency
E03 on Alpha Intec 40GS2

Your boiler has detected that the exhaust gases are becoming too hot, so it has safely shut itself down to prevent damage.

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 intervention

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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