Low
D.91 on Vaillant Combi Compact 242EB

Your boiler is displaying a communication status message regarding an external weather sensor and does not indicate a breakdown.

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

DCF status with connected external probe

DIY fix possible

Check if the outdoor temperature sensor is covered by snow or debrisObserve if the display changes to a temperature reading after a few minutesRestart the boiler to see if the status cleared

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Related fault codes

D.90View →F.28View →

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