High
Neon 2 lit (NO) on Saunier Duval Xeon 30ff

Your boiler has stopped working because a safety sensor has detected that the unit became too hot and triggered an automatic shutdown.

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

For gravity domestic hot water systems only, check continuity of yellow link. For fully pumped systems, check overheat reset. If satisfactory replace overheat device.

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 1View →Neon 3View →

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