Low
d.47 on Vaillant Home System

Your boiler is displaying the current reading from its outdoor weather sensor to adjust how it heats your home.

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: Current value

DIY fix possible

This fault may be fixable without an engineer. Check your manual first.

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Related fault codes

F.27View →F.28View →F.29View →

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