Low
Vitodens 200-W on Viessmann Vitola Biferral

Your boiler is struggling to accurately measure the water temperature after it leaves the main unit, which may cause your heating to be less efficient or inconsistent.

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

Regulates without supply temperature sensor (low-loss header)

Engineer required

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

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