Low
d.6 on Vaillant ecoTEC Pro / ecoTEC Plus

This code is not actually an error; it is simply showing you the temperature your boiler is currently set to reach for your hot water.

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

Hot water temperature target value in °C

From this model's manual
Verified against the Vaillant Ecotec Combi installation & service manual, page 44.
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

Recognise that this is a status code rather than a faultCheck your boiler display settings if you wish to adjust your target hot water temperaturePress the 'i' button on your boiler control panel to return to the normal operating display

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