BoilerFaultCodesSime ALL 14 Fault Code
Also written as ALL14 — same fault.
The Sime ALL 14 fault code means: your boiler has detected an issue with the sensor that monitors the temperature of the exhaust fumes, meaning it has shut down as a precaution to ensure safe operation.. It appears on 9 Sime models in our database.
Technical description: Exhaust sensor (SF) fault
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Avoid the next call-out bill
A cover plan would handle faults like ALL 14: no call-out fees, no surprise bills.
Affiliate links. We may earn a commission at no extra cost to you.
Sime models that show the ALL 14 fault code
Click a model for the full fault code list and model-specific repair notes.
- iQE Simplicity 20T Repair: £120-£400
- Murelle Advanced HE Combi Repair: £150-250
- Murelle Advanced HE MkII Combi Repair: £120-220
- Murelle Elite HE 35T System Repair: £150-250
- Murelle Elite HE Combi Repair: £120-250
- Murelle HE Combi with Cylinder Repair: £150-250
- Murelle HE Regular Repair: £120-220
- Murelle HE System Repair: £150-250
- Murelle Revolution 30 Repair: £150-250
Source
Sime ALL 14 fault code information on this page is sourced and cross-checked against the official Sime service / installation manuals for each affected model.
- Sime iQE Simplicity 20T manual (PDF)
- Sime Murelle Advanced HE Combi manual (PDF)
- Sime Murelle Advanced HE MkII Combi manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026