Low
d.71 on Vaillant ecoMAX 635

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.

Technical description

Max. target value for heating-system flow temperature

DIY fix possible

Check the thermostat settings to ensure the target temperature is correctAdjust the maximum flow temperature via the boiler control panel if necessaryRefer to the user manual to see if a specific heating limit has been set

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