High
E 10 on Ariston Genus 30 Plus

Your boiler has detected that an external safety sensor, typically linked to your underfloor heating system, has triggered, causing the system to stop working to prevent overheating.

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

Contact open in the floor overheat safety device circuit (Flora room thermostat)

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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