Medium
AL 42 on Sime Brava One HE

Your boiler's controls have detected a stuck or malfunctioning button on the front panel, preventing it from processing your commands.

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

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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 depressed.Gently wipe the control panel with a dry, lint-free cloth to ensure no debris is jamming the buttons.Turn the electrical power to the boiler off and back on again to reset the electronic board.

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Related fault codes

AL 40View →AL 41View →

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