Low
D.4 on Vaillant Combi Compact 242EB

Your boiler is currently reading the live temperature from the warm start sensor, which is a normal status message rather than an actual fault code.

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

Current temperature for warm stat sensor

DIY fix possible

Check if the comfort or 'warm start' mode is intentionally switched onPress the reset button if the boiler appears stuck on this displayMonitor to see if the display changes to a standard temperature reading after a few minutes

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Related fault codes

D.0View →D.40View →D.41View →

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