Medium
AL 42 on Sime Brava Slim HE System

Your boiler has detected that one of its control buttons is stuck or pressed down for too long, preventing the system 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 Brava Slim He 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 'in' position.Gently wipe the control panel with a dry cloth to remove any debris or sticky residue.Turn the boiler off at the fused spur switch, wait 30 seconds, and turn it back on to reset the electronics.

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Related fault codes

AL 03View →AL 40View →

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