Biasi Er03+RESET Fault Code
Also written as ER03RESET — same fault.
The Biasi Er03+RESET fault code means: your boiler has detected a general internal fault that has caused the system to lock out for safety.. It appears on 1 Biasi model in our database.
Technical description: Other faults
DIY fix possible
Press and hold the 'Reset' button for 5 seconds to clear the temporary errorCheck that your electricity supply is stable and the boiler fuse hasn't trippedEnsure there is credit on your gas meter (if applicable)
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Gas Safe Register →Biasi models that show the Er03+RESET fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Biasi Er03+RESET fault code information on this page is sourced and cross-checked against the official Biasi service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026