BoilerFaultCodesRemeha 03 Fault Code
The Remeha 03 fault code means: your boiler has detected an electrical safety issue with its power connection and is shutting down to prevent damage or danger.. It appears on 2 Remeha models in our database.
Technical description: Mains supply not correctly earthed. Control unit faulty.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Remeha models that show the 03 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Remeha 03 fault code information on this page is sourced and cross-checked against the official Remeha service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026