BoilerFaultCodesYour boiler is currently set to a professional test mode for servicing and is not in its normal operating state.
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: Service Mode - Upper Fan
What causes this fault?
This code appears when the boiler has been manually put into a high-performance test mode by a heating engineer during a service or inspection. It occurs because the boiler is bypasssing its normal temperature controls to run the fan at maximum speed for flue gas analysis. It is not a mechanical failure but rather a status indicator that the unit is being tested.
DIY fix possible
Locate the 'Mode' or 'Reset' knob/button on the front panel.Turn the selector knob away from the 'Service' or 'Spanner' icon back to 'Auto' or 'On'.Press the 'Reset' button once if the code persists after changing the mode.
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