Low
d.35 on Vaillant Home System

Your boiler is simply showing you whether it is currently sending heat to your radiators, your hot water tank, or both at the same time.

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

Position of the diverter valve: 0=Heating, 40=Mid-position (parallel operation), 100=Domestic hot water

DIY fix possible

This fault may be fixable without an engineer. Check your manual first.

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Related fault codes

d.33View →d.34View →d.70View →

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