Low
D.47 on Vaillant Combi Compact 242EB

Your boiler is having trouble communicating with the outdoor sensor that helps it adjust to the weather, meaning your heating might not be as efficient as usual.

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

Outside temperature with weather compensator – Vaillant controller only

DIY fix possible

Locate the outdoor sensor on your external wallCheck for any visible damage to the sensor unit or loose wiresGently wipe away any heavy dirt or debris covering the sensor

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Related fault codes

D.40View →D.41View →

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