BoilerFaultCodesSime ALL 08 Fault Code
Also written as ALL08 — same fault.
The Sime ALL 08 fault code means: your boiler is failing to light because it cannot detect a flame, so it has shut down as a safety precaution to prevent a gas build-up.. It appears on 8 Sime models in our database.
Technical description: FLAME DETECTION ERROR
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 ALL 08 fault code
Click a model for the full fault code list and model-specific repair notes.
- Murelle Advanced HE Combi Repair: £150-£300
- Murelle Advanced HE MkII Combi Repair: £120-250
- Murelle Elite HE 35T System Repair: £120-250
- Murelle Elite HE Combi Repair: £150-300
- Murelle HE Combi with Cylinder Repair: £150-300
- Murelle HE Regular Repair: £120-250
- Murelle HE System Repair: £150-250
- Murelle Revolution 30 Repair: £120-250
Source
Sime ALL 08 fault code information on this page is sourced and cross-checked against the official Sime service / installation manuals for each affected model.
- Sime Murelle Advanced HE Combi manual (PDF)
- Sime Murelle Advanced HE MkII Combi manual (PDF)
- Sime Murelle Elite HE 35T System manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026