Low
d.71 on Vaillant ecoFIT Pure 835

Your boiler is notifying you that it has reached the maximum temperature allowed for your heating system, so it is temporarily limiting itself for safety.

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.

What the manual says

Manufacturer manual

Maximum heating flow set target temperature

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 31.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Ensure all radiator valves (TRVs) are open to allow water to circulateCheck that the magnetic system filter is not blockedLower the heating flow temperature setting slightly on the front control panel

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