High
F11 on Saunier Duval Semia Condens F30 E

Your boiler's main internal computer and the front control display have lost their ability to talk to each other, preventing the system from operating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

User interface connection fault. Check wiring between mainboard and user interface

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F13View →

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