Medium
AL 42 on Sime Murelle Pro HE R MkII System

Your boiler has detected that one of the buttons on the control panel is stuck or faulty, which is preventing the unit from working correctly.

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 R Mkii System installation & service manual, page 40.
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 check each button on the front panel to see if any are stuck in the pressed position.Gently press and release every button several times to ensure they move freely and click.Try resetting the boiler by turning the power off at the fused spur switch for 30 seconds and then back on.

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Related fault codes

AL 40View →AL 41View →

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