BoilerFaultCodesSime AL 72 Fault Code
Also written as AL72 — same fault.
The Sime AL 72 fault code means: your boiler has detected that a temperature sensor isn't correctly touching the pipe it needs to monitor, preventing it from reading the water temperature accurately.. It appears on 14 Sime models in our database.
Technical description: Incorrect positioning of the delivery sensor — verify sensor is correctly attached to delivery pipe
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 AL 72 fault code
Click a model for the full fault code list and model-specific repair notes.
- Brava One HE Repair: £90-170
- 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: £90-160
- Giulia Combi 30 Repair: £90-180
- Halstead Trio Repair: £90-160
- Mia 30 Repair: £90-180
- Murelle One HE Repair: £90-160
- Murelle Pro HE 25 HO Repair: £90-160
- 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 72 fault code information on this page is sourced and cross-checked against the official Sime service / installation manuals for each affected model.
- Sime Brava One HE manual (PDF)
- Sime Brava Slim HE System manual (PDF)
- Sime Dewy 30/130 HE FS manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026