Medium
AL 42 on Sime Murelle One HE

Your boiler has detected that one of the buttons on the control panel is stuck or faulty, which is preventing the system from operating 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 One He installation & service manual, page 43.
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

Check all buttons on the front panel to see if any are physically stuck in the 'pressed' position.Gently press and release every button several times to ensure they move freely.Restart the boiler using the reset button to see if the error clears.

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Related fault codes

AL 40View →AL 41View →

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