Low
18 on Viessmann Vitodens 100-W

Your boiler has lost the signal from the weather sensor outside your home and is now running on a default setting.

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

Constant mode: Outdoor temperature sensor lead broken

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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