BoilerFaultCodesYour boiler is currently stuck between modes and is trying to decide whether to send heat to your radiators or your hot water tank.
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: Set diverter valve position
What causes this fault?
This code appears when the boiler's internal electronics lose track of where the diverter valve is positioned, often following a power cut or a software reset. It essentially means the control board is performing a self-check to confirm whether it should be sending heat to your taps or your radiators. In some cases, it can trigger if the mechanical motor that moves the valve is beginning to stiffen or seize up.
This code is slightly more common in autumn when homeowners turn their heating back on for the first time, forcing a valve that has been stationary all summer to move.
DIY fix possible
Locate the grey selector knobs on the front of the boiler control panelTurn the radiator temperature dial slightly up or down to trigger a new demandWait 60 seconds to see if the display changes to a standard temperature reading
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