Low Warning
81:3 on Viessmann Vitodens 050-W

Your boiler is having trouble synchronizing its clock with other connected parts of your heating system.

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

Accept time via LON

What causes this fault?

This fault happens when there is a breakdown in communication between the boiler and other smart controllers or expansion modules connected via the LON network. It is usually caused by an incorrect setting in the boiler's menu or a conflict in how the devices are trying to synchronize their internal clocks. In most cases, it is a configuration error rather than a physical part failure.

DIY fix possible

Navigate to the 'Settings' or 'Menu' on your control panelLook for the 'Time' and 'Date' settingsManually update the time and date then save the settings to clear the notification

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