Low
D.40 on Vaillant Combi Compact 242EB

Your boiler is displaying the current temperature it is aiming to reach for your heating or hot water, rather than a system 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.

Technical description

Flow temperature target value

DIY fix possible

Check if the heating or hot water is running normallyPress the 'i' button to exit the information displayMonitor the boiler to see if it moves past the information code to show a temperature

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Related fault codes

D.41View →S.4View →

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