Low
D.40 on Vaillant Combi Compact 282EB

Your boiler is displaying its current target heating temperature rather than a fault code, meaning it is operating as designed.

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 room thermostat is calling for heatMonitor the display to see if the status changes as the boiler warms upConfirm that your heating and hot water are functioning as expected

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Related fault codes

D.41View →S.04View →

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