BoilerFaultCodesYour boiler is not broken; it is simply in a special service mode used by engineers when they are preparing to replace internal parts.
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: To move the diverter valve to mid-position for replacement
What causes this fault?
This code appears when someone has manually activated the diverter valve service function, usually by pressing a specific combination of buttons. It is a programmed setting that moves internal components into a neutral position to allow an engineer to safely drain the unit and replace parts. It is not caused by a mechanical failure but by the boiler being placed into a pre-service state.
DIY fix possible
Turn the mains power to the boiler offWait 30 secondsTurn the power back on to reset the boiler to normal operation
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