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

From this model's manual
Verified against the Sime/Sime Brava One He installation & service 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 →

All 49 fault codes on the Brava One HE

Seeing a different code? Every code this model can display, in one place.

06AL 00AL 01AL 02AL 03AL 04AL 05AL 06AL 07AL 08AL 09AL 10AL 11AL 12AL 13AL 14AL 15AL 18AL 28AL 30AL 37AL 40AL 41AL 43AL 44AL 56AL 57AL 62AL 72AL 74AL 77AL 78AL 79AL 80AL 81AL 82AL 83AL 84AL 88AL 89AL 90AL 92AL 93AL 95AL 96AL 98AL 99SE

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