Low
Cd on Viessmann Vitodens 242-F FB2B

Your boiler has lost its connection to the remote control or internet monitoring system, so you may not be able to adjust settings via your app or external thermostat.

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.

What the manual says

Manufacturer manual

Communication error, Vitocom 100 (KM BUS)

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 242 F Fb2b installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check that your internet router is switched on and workingEnsure the Vitocom 100 communication module is firmly plugged into the boilerTurn the boiler power off and back on again to restart the communication link

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Related fault codes

BCView →CFView →D1View →

All 66 fault codes on the Vitodens 242-F FB2B

Seeing a different code? Every code this model can display, in one place.

9A9C9E9F58599294A2A4A7A8A9b0b1b4b5b7b8bAbbbCbdbEbFC1C2C3C4CFd6d7d8dAdbdCdddEdFE0E1E3E4E5E6E7E8EAEbECEdEEEFF0F1F2F3F7F8F9FAFCFdFEFF

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