Medium
F.430 on Viessmann Vitodens 222-F B2TF

Your boiler has lost its connection to its internal communication module, meaning it cannot properly send or receive control signals.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Communication error, 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.

DIY fix possible

Switch the boiler off at the fused spur or main power switch.Wait for 60 seconds.Switch the boiler back on and wait for the system to reboot to see if the connection is restored.

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