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d.34 on Vaillant ecoFIT Pure 835

Your boiler is displaying an information code that shows the current speed of the internal fan to help diagnose performance.

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

Value for the fan speed

DIY fix possible

Press the 'Back' or 'Reset' button to return to the standard temperature display.If the code persists or prevents the boiler from starting, turn the power off and back on.

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Related fault codes

d.33View →F.32View →

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