BoilerFaultCodesYour boiler is currently in an advanced settings mode used by engineers and does not indicate a mechanical fault with the heating system.
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: Activation of the second diagnostic level
What causes this fault?
This code appears when someone has accessed the boiler's deeper programming menu to adjust technical parameters or check sensor data. It acts as a status indicator rather than a mechanical failure, showing that the display is currently set to show advanced diagnostic information. Your heating and hot water will continue to function normally once the engineer exits this menu.
DIY fix possible
Press the 'Back' button (represented by an arrow) to exit the menu.If the screen does not revert, press and hold the 'Reset' button for five seconds.Restart the boiler using the main power switch if the display remains stuck in the diagnostic menu.
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