Low
D.3 on Vaillant Combi Compact 242EB

Your boiler is currently showing you the temperature of the hot water as it flows through the system rather than a 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

Hot water flow temperature reading

DIY fix possible

No action is required as this is a status message, not a fault.Wait for the hot water tap to be turned off for the display to return to the heating temperature.If the code persists when no water is running, check for a leaking or dripping tap.

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Related fault codes

D.0View →D.1View →D.2View →

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