BoilerFaultCodes EE0099 High
Boiler Fault Code EE0099
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code EE0099 appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler's sensor that monitors water returning from your radiators is malfunctioning, which is causing the system to stop heating your home as a safety precaution. (As reported on Ariston Clas One)
Pick your boiler brand for the EE0099 fix
Source
Information for the EE0099 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