Er03+RESET High

Boiler Fault Code Er03+RESET

Also written as ER03RESET — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code Er03+RESET 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 has detected a general internal fault that has caused the system to lock out for safety. (As reported on Biasi Activa)

Pick your boiler brand for the Er03+RESET fix

Biasi Er03+RESET 1 model

Source

Information for the Er03+RESET 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