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.

Technical description

Maximum heating flow set target temperature

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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F.20View →

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