Emergency
F16 on Saunier Duval Semia Condens F30 E

Your boiler is struggling to turn off its internal flame correctly, which suggests a component meant to cut off the gas supply has failed.

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.

Technical description

Flame detection fault (flame presence for more than 5 seconds after burner stopped). Gas valve defective

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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