High
E 09 on Ariston Genus 30 Plus

Your boiler has detected an electrical fault in the system that measures the temperature of the water returning to it, causing it to stop heating as a safety precaution.

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

Short circuit on heating return sensor

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

E 08View →E 10View →

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