Low
77:1 on Viessmann Vitodens 300-W

Your boiler's internal communication system has detected two components trying to use the same identification number, causing a minor configuration conflict.

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

LON user number

DIY fix possible

Navigate to the boiler control panel menu.Perform a system reset to see if the communication error clears automatically.If you have recently added a new remote control or smart module, check the manual for how to assign a unique participant number.

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