BoilerFaultCodesSime 63 Fault Code
The Sime 63 fault code means: your boiler is currently in a special viewing mode that lets you see its settings without changing them, rather than indicating an actual mechanical fault.. It appears on 4 Sime models in our database.
Technical description: Final user level 2 - This block (1) can be activated to display all the parameters without modifying them.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Sime models that show the 63 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Sime 63 fault code information on this page is sourced and cross-checked against the official Sime service / installation manuals for each affected model.
- Sime Dewy 30/130 HE FS manual (PDF)
- Sime Dewy 30/50 HE WM manual (PDF)
- Sime Planet Dewy BFR manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026