High
Neon 1 lit (NO) on Saunier Duval Xeon 30ff

Your boiler is failing to start because it is not receiving a consistent or correctly connected power supply.

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

Isolate electrical supply and check for correct polarity. Turn the boiler thermostat to its maximum setting. Also check fuses. Correct power supply 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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Related fault codes

Neon 2View →Neon 3View →

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