Low
d.5 on Vaillant ecoMAX

Your boiler is simply displaying the current temperature setting for your heating water and is not experiencing 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

Flow temperature setting

From this model's manual
Verified against the Vaillant Ecomax 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 the boiler interface to return to the standard display modeCheck your thermostat settings to ensure your heating is programmed as requiredNo further action is needed as this is a status code, not an error

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