Low Warning
7b:0 on Viessmann Vitodens 300-W

Your boiler is having difficulty communicating the correct time over its internal network system, which might affect your heating schedules.

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

Do not send time to LON

What causes this fault?

This fault occurs when there is a configuration error in the boiler's communication settings, specifically regarding how it shares time and date information with other linked components. It usually happens because the control system is trying to send a time signal to a network module that isn't set up to receive it, or there is a minor data mismatch between the internal boards.

DIY fix possible

Check that the date and time settings on the main boiler control panel are correctPerform a simple reset of the boiler using the power buttonIf you have a Vitotrol room thermostat, ensure it is powered and showing the correct time

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Related fault codes

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