Low
d.71 on Vaillant ecoMAX System 612

Your boiler is limiting the maximum temperature it allows for the water circulating through your radiators to prevent the system from getting too hot.

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

Max. target value for heating-system flow temperature

From this model's manual
Verified against the Vaillant Ecomax 613 installation & service manual, page 47.
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

Check the maximum flow temperature setting in the user menuAdjust the heating temperature dial or digital setpoint to your preferenceConsult the user manual to ensure the setting matches your system requirements

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