Medium
AL 42 on Sime Murelle Pro HE System R

Your boiler has detected that one of its control buttons is stuck or faulty, which is preventing the control panel 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 System R installation & service manual, page 33.
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 stuck in the 'pressed' positionGently wipe the control panel with a dry cloth to ensure no debris is jamming the buttonsTurn the electrical power to the boiler off and back on to reset the control board

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Related fault codes

AL 40View →AL 41View →

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