Low Warning
95:0 on Viessmann Vitodens 300-W

Your boiler has lost its connection to its remote communication module, meaning you cannot control your heating via the app, but your hot water and heating should still work manually.

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

Without Vitocom 100 communication interface

What causes this fault?

This fault occurs when the boiler's main control board expects to be talking to an external communication module, like a Vitocom 100, but cannot find it on the system. The most common reason is a loose or damaged data cable between the module and the boiler, or the internal communication component has lost power and stopped sending a signal.

DIY fix possible

Check that your internet router is switched on and workingEnsure the Vitocom 100 module is plugged in and has powerIdentify if the communication cable between the boiler and the module has become loose

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95:1View →

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