Low
10 on Viessmann Vitodens 300-W

Your boiler's outside temperature sensor has developed an electrical fault, causing the system to behave as if it is exactly 0°C outdoors regardless of the actual weather.

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

Controls according to 0°C outside temperature: Outside temperature sensor shorted out

Engineer required

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

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Related fault codes

18View →0FView →

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