Low Information
D.83 on Vaillant ecoTEC

Your boiler is providing a status update to show it is currently heating up the water for your taps.

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

Burner start up in hot water mode

What causes this fault?

This code appears when the boiler detects a demand for hot water and begins the ignition sequence to heat it. It is not actually a fault, but a status message indicating that the internal burner is firing up to provide water for your taps or shower. Once the water reaches the required temperature, the code will usually change or disappear.

DIY fix possible

This fault may be fixable without an engineer. Check your manual first.

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Related fault codes

D.80View →D.81View →D.82View →

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