Low Warning
95:1 on Viessmann Vitodens 333-F

Your boiler has detected an issue communicating with its remote control or internet connection module during the initial setup process.

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

With Vitocom 100 communication interface; automatic recognition

What causes this fault?

This fault occurs when the boiler's main control board fails to detect or synchronise with the plug-in internet module during its startup sequence. The most common reason is a loose internal data cable or a communication handshake error between the boiler and the Wi-Fi interface.

DIY fix possible

Check that your internet router is switched on and workingEnsure all cables connecting the Vitocom module to the boiler are firmly plugged inTurn the boiler power off and back on again to trigger a fresh automatic search

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