Low
d.40 on Vaillant ecoMAX 613

This code is simply showing you the current temperature of the water inside your boiler system, rather than indicating a fault.

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

Check your boiler display settings to ensure it is in standard operating modePress the 'i' button to return to the main status viewNo physical intervention is required as this is a status display rather than a breakdown

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Related fault codes

d.41View →d.00View →

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