Medium
AL 42 on Sime Murelle Pro HE Combi

Your boiler has detected that one of its control buttons is stuck or faulty, which is preventing you from changing settings or operating the unit properly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Button fault — verify all control buttons function; check PCB

From this model's manual
Verified against the Sime Murelle Pro He Combi installation & service manual, page 32.
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

Carefully press and release each button on the control panel to see if any are physically stuck or jammed.Gently wipe the control panel with a dry, lint-free cloth to ensure no debris is interfering with the buttons.Turn the power supply to the boiler off and back on again to reset the electronic controls.

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Related fault codes

AL 40View →AL 41View →

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