Low
25:1 on Viessmann Vitodens 333

Your boiler is struggling to read the temperature outside, which means it cannot automatically adjust your heating to match the weather conditions.

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

Recognition of outside temperature sensor and fault monitoring

Engineer required

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

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