High
Does fan Hunt? (YES) on Saunier Duval Xeon 30ff

Your boiler is struggling to start up correctly because its internal control brain is failing to manage the air extraction system properly.

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

Replace printed circuit board.

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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