High
Neon 1 lit on Saunier Duval Xeon 120 FF

Your boiler is failing to detect an electrical power supply, meaning it cannot switch on or operate your heating and 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

Power supply problem. Correct power supply problem if neon 1 is not lit.

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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