BoilerFaultCodesYour boiler is currently set to a 'showroom' mode which allows the display to work for demonstration purposes but prevents the burner from actually firing to provide heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Maintenance:Demomode
What causes this fault?
This fault occurs when the boiler's software is accidentally placed into 'Showroom Mode', which is a setting intended for shop displays only. It means the control board thinks it should only light up the screen for demonstration rather than actually igniting the gas to heat your home. This is usually caused by a technician forgetting to deactivate the setting during installation or a mistake within the service menu.
DIY fix possible
Press and hold the 'i' and '+' buttons simultaneously for about 5 seconds.The screen should show 'd.00' or similar; use the '+' button to navigate to 'd.91'.Press the 'i' button to view the setting; if it shows '1', change it to '0' using the '-' button.Press and hold 'i' to save the change, then press 'i' and '+' together to exit.
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