Emergency
13 on Sime Murelle EV HE Combi

Your boiler has detected that the flue gases are getting too hot, so it has safely shut itself down to prevent potential overheating or dangerous exhaust issues.

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

ACTIVATION OF THE EXHAUST FUMES SENSOR ERROR

From this model's manual
Verified against the Sime Murelle Ev He Combi installation & service manual, page 32.
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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