High
F13 on Saunier Duval Semia Condens F30 E

Your boiler's computer is having trouble communicating with its internal parts, meaning the system has safely shut down to prevent incorrect operation.

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

Main board connection fault. Main board defective. Check connection and wires

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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