High
F18 on Saunier Duval Semia Condens F30 E

Your boiler's electronic display panel is failing to communicate with the main computer, which prevents the boiler from operating correctly.

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 fault. Faulty 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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