BoilerFaultCodesYour boiler is currently set to a manual testing mode used by engineers to check emissions, which prevents it from operating normally.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Chimney sweep demand
What causes this fault?
This code appears when the 'Chimney Sweep' mode has been manually activated on the boiler's control panel. It is a setting used by engineers during a service to force the boiler into maximum or minimum output for emissions testing, which overrides your normal heating and hot water settings. If this has appeared unexpectedly, it is usually because the button was pressed by accident or the mode was not exited after a recent service.
This code is frequently seen during the autumn and winter months when annual service visits and safety checks are most commonly scheduled.
DIY fix possible
Locate the 'Chimney Sweep' button (icon looks like a brush) on the touch screen display.Press and hold the button for approximately 3 to 5 seconds.The display should return to the standard temperature screen once the mode is deactivated.
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