High
Neon 2 NOT lit on Saunier Duval Xeon 120 FF

Your boiler has automatically shut itself down because it detected that it is getting too hot, likely due to a flow restriction or a failing safety sensor.

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

Overheat cut off device tripped or thermostat, overheat cut off device faulty

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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