Low Information
D.3 on Vaillant ecoTEC plus Regular

Your boiler is simply showing that it is currently preparing or providing hot water to your taps or cylinder.

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.

Technical description

Hot water flow temperature reading

What causes this fault?

This occurs when the boiler sensors detect that there is a demand for hot water, either for your taps or to heat your water cylinder. It is a normal status message indicating the internal components are currently measuring the temperature of the water being sent to your house. It is not a sign of a breakdown, but rather the boiler confirming it is doing its job.

DIY fix possible

Check if your hot water is running or the cylinder is heating upWait for the hot water demand to finishObserve if the screen changes back to a temperature or different status once finished

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Related fault codes

D.0View →D.4View →

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