Low
F.431 on Viessmann Vitodens 222-F B2TF

Your boiler is working fine, but it is failing to communicate with your smart home or external heating control system.

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

Normal operation in line with set values of heat generator. Communication error KNX gateway.

From this model's manual
Verified against the Viessmann Vitodens 222 F B2tf installation & service manual, page 101.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.432View →F.433View →

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