High
Neon 1 NOT lit on Saunier Duval Xeon 120 FF

Your boiler is not receiving any power, meaning it is completely turned off and cannot provide 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

Fault with mains supply or PCB fuse

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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