BoilerFaultCodesSime AL 05 Fault Code
Also written as AL05 — same fault.
The Sime AL 05 fault code means: your boiler has detected a problem with the temperature sensor that monitors the water being sent to your taps and radiators, causing it to stop working as a safety precaution.. It appears on 22 Sime models in our database.
Technical description: Delivery sensor (SM) fault — check connections; replace sensor
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A cover plan would handle faults like AL 05: no call-out fees, no surprise bills.
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Sime models that show the AL 05 fault code
Click a model for the full fault code list and model-specific repair notes.
- Brava DGT HE Repair: £90-160
- Brava One HE Repair: £90-160
- Brava Slim HE Regular Repair: £90-160
- Brava Slim HE System Repair: £90-160
- Dewy 30/130 HE FS Repair: £90-160
- Dewy 30/50 HE WM Repair: £100-£180
- Ecomfort Plus HE EV Combi Repair: £90-160
- Ecomfort System Plus HE EV Repair: £90-160
- Format DGT HE Combi Repair: £90-160
- Format DGT HE System Repair: £90-160
- Giulia Combi 30 Repair: £90-160
- Halstead Trio Repair: £90-160
- iQE Comfort 30 Repair: £120-220
- Meridian HE Repair: £90-160
- Metropolis DGT 25 BF Repair: £90-160
- Mia 30 Repair: £0-120
- Murelle One HE Repair: £90-160
- Murelle Pro HE 25 HO Repair: £90-170
- Murelle Pro HE Combi Repair: £90-160
- Murelle Pro HE MkII Combi Repair: £90-160
- Murelle Pro HE R MkII System Repair: £90-£160
- Murelle Pro HE System R Repair: £90-160
Source
Sime AL 05 fault code information on this page is sourced and cross-checked against the official Sime service / installation manuals for each affected model.
- Sime Brava DGT HE manual (PDF)
- Sime Brava One HE manual (PDF)
- Sime Brava Slim HE System manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026