BoilerFaultCodes 03E High
Boiler Fault Code 03E
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 03E appears across 1 boiler brand and 7 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning The boiler's internal sensor that monitors water temperature or flow has failed, meaning the system cannot safely regulate heat. (As reported on Ravenheat HE 80/90 / 25-30s)
Pick your boiler brand for the 03E fix
Source
Information for the 03E 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