BoilerFaultCodesYour boiler is currently running at a fixed power level for testing purposes and is not responding to your normal thermostat settings.
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: The boiler is in chimney sweep mode
What causes this fault?
This code appears when the manual service switch on the boiler's control panel has been physically moved into the 'chimney sweep' position. This is usually done by an engineer during a service to force the boiler to run at its maximum or minimum output for testing. It isn't a mechanical failure, but rather a notification that the boiler is locked into this manual testing mode.
DIY fix possible
Locate the button with a soot-cloud or chimney icon on the control panel.Press and hold the chimney sweep button for at least two seconds.The display should return to the normal temperature reading once the mode is deactivated.
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