Low
F.430 on Viessmann Vitodens 100-W WB1A

Your boiler is having trouble communicating with its smart control connectivity system, which means it cannot link up to external automation devices or remotely adjust your settings.

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

Connection of automation modules not possible | Communication error, gateway

From this model's manual
Verified against the Viessmann Vitodens 100 W Wb1a installation & service manual, page 93.
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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