BoilerFaultCodes E 09 High
Boiler Fault Code E 09
Also written as E09 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code E 09 appears across 2 boiler brands and 8 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler has stopped working because one of its internal temperature sensors has developed an electrical fault and can no longer monitor the water coming back from your radiators. (As reported on Ariston Genus 27)
Pick your boiler brand for the E 09 fix
Source
Information for the E 09 fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026