Low
d.40 on Vaillant ecoTEC plus aquaPLUS

Your boiler is currently displaying the live temperature of the water flowing through the system rather than a fault code.

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 Ecotec Plus Aquaplus installation & service manual.
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

No action is required as this is an informational status code.Press the 'i' button to exit the information menu if you wish to see the system pressure.If the boiler is not firing, check that your thermostat is turned up and calling for heat.

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Related fault codes

d.41View →S.04View →S.24View →

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