High
Main burner not operating on Saunier Duval Xeon 30ff

Your boiler is failing to ignite because it cannot signal the gas valve to open, meaning you currently have no heating or hot water.

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

Multi-functional control/harness problem

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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