Your boiler is accidentally trying to use a feature it doesn't have, which is usually caused by a minor electronic glitch or a recent settings change.
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: This feature is not required on this appliance.
What causes this fault?
This fault occurs when the boiler's internal computer becomes confused and tries to activate a 'flue luxury' feature that wasn't designed for this specific model. It is usually triggered by a brief electrical surge or if the boiler's software settings have accidentally been changed during a service or repair. Most of the time, the boiler simply needs to be told which model it is again to clear the error.
DIY fix possible
Locate the reset button on the boiler control panel.Press and hold the reset button for 2 to 5 seconds.Wait for the boiler to restart; the code should disappear if it was a temporary software error.
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