Low
d.15 on Vaillant Home System

Your boiler is simply displaying the current operating speed of its internal pump as a percentage, which is a normal status message rather than an error.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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 speed: Current value in %

DIY fix possible

No action is required as this is an information code.Press the 'Back' or 'Menu' button to return to the main temperature display.If the code persists and the boiler isn't heating, try a simple reset.

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d.01View →d.14View →d.19View →

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