Low
d.71 on Vaillant ecoFIT Pure 435

Your boiler is notifying you that it has reached the maximum temperature limit set for your central heating water.

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

Check if your radiator valves are fully open to allow heat to circulateReduce the heating temperature setting on the boiler control panelEnsure there is enough water pressure in the system (typically 1.0 to 1.5 bar)

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