Low
AL 03 on Sime Mia 30

Your boiler is notifying you that a safety fault occurred recently and the system has saved this record in its memory.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Previous activated alarm/fault

From this model's manual
Verified against the Sime Mia 30 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Press and hold the 'Reset' button for a few seconds to clear the alertMonitor the boiler to see if a more specific active fault code appearsEnsure your system pressure is between 1 and 1.5 bar

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AL 01View →AL 02View →AL 05View →

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