Emergency
03 on Alpha E-Tec Plus 10 / 18

Your boiler has switched itself off because the waste gases are getting too hot, which is a safety mechanism to prevent internal damage.

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 sensor intervention (flue temperature too high)

From this model's manual
Verified against the Alpha E Tec Plus 10 18 installation & service manual, page 47.
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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