Emergency
ALL 13 on Sime Murelle HE System

Your boiler has detected that the gases produced during burning are not escaping properly, so it has safely shut down to prevent the build-up of dangerous fumes.

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 He System installation & service manual, page 29.
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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