High
Neon 4 lit on Saunier Duval Xeon 120 FF

Your boiler has stopped working because the internal control board is failing to send electrical power to the gas valve.

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 4 lit? NO: Is there 230V~ between pilot multi-functional control solenoid blue and brown connections? NO: Isolate supply, test harness continuity. If satisfactory 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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