Emergency
05 on Saunier Duval Semia Condens F30 E

Your boiler has detected that it is getting dangerously hot and has shut itself down to prevent damage or a safety hazard.

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

The boiler is overheating and the Safety Thermostat has triggered OR The boiler flue is overheating and the Flue Safety Thermostat has triggered.

From this model's manual
Verified against the Saunier Duval Semia Condens F30 E installation & service manual.
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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