BoilerFaultCodesSime AL 09 Fault Code
Also written as AL09 — same fault.
The Sime AL 09 fault code means: your boiler has stopped working because water is not moving around the system properly, which is preventing the unit from heating up safely.. It appears on 14 Sime models in our database.
Technical description: No water circulating in the system — check pump rotation; verify pump not seized; check impeller; check filter
DIY fix possible
Check that your system pressure is between 1.0 and 1.5 bar on the pressure gauge.Ensure all radiator valves and isolation valves under the boiler are fully open.Gently bleed your radiators to remove any trapped air that might be blocking flow.
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Sime models that show the AL 09 fault code
Click a model for the full fault code list and model-specific repair notes.
- Brava One HE Repair: £150-£350
- Brava Slim HE Regular Repair: £120-£350
- Brava Slim HE System Repair: £180-£350
- Dewy 30/130 HE FS Repair: £150-£350
- Dewy 30/50 HE WM Repair: £150-£350
- Giulia Combi 30 Repair: £180-350
- Halstead Trio Repair: £180-350
- Mia 30 Repair: £120-250
- Murelle One HE Repair: £180-350
- Murelle Pro HE 25 HO Repair: £150-£350
- Murelle Pro HE Combi Repair: £180-£350
- Murelle Pro HE MkII Combi Repair: £180-£450
- Murelle Pro HE R MkII System Repair: £150-£350
- Murelle Pro HE System R Repair: £150-£350
Source
Sime AL 09 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