High
Neon 1 lit on Saunier Duval Xeon 30ff

Your boiler is currently receiving no electrical power, meaning it cannot operate your 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

Is neon 1 lit? NO: Correct power supply problem. YES: Is neon 2 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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