Low
AL 05 on Sime Mia 30

Your boiler is notifying you that a fault occurred previously, though it may not be active right now.

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, page 44.
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 history alertMonitor the boiler display to see if a more specific error code appearsEnsure your system pressure is between 1 and 1.5 bar

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