Low
d.40 on Vaillant ecoMAX 824E

This code is simply showing you the current temperature of the water moving through your heating system and is not an error message.

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

Actual 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

Press the 'i' button on your boiler display to return to the standard operating viewObserve the boiler for a moment to ensure it proceeds with normal heating or hot water cyclesNo further action is required as this is a normal display status

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