Low
d.01 on Vaillant ecoFIT Pure 425

Your boiler is simply finishing its normal cooling down cycle after a period of heating, which is a standard operational state and not a fault.

Monitor it

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

Pump overrun in heating mode

DIY fix possible

No action is required as this is a status code, not an error.Wait for the pump symbol to disappear once the system has cooled down.If the code never disappears, contact a professional to check the pump settings.

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