Low
d.71 on Vaillant ecoFIT Pure 425

Your boiler's heating temperature has been set to a limit that is too high for the system to safely handle, often resulting in an automatic shutdown to prevent overheating.

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

Navigate to the boiler control panelLocate the radiator temperature dial or digital settingTurn the temperature down to 75°C or lower to clear the warning

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