Low
0F on Viessmann Vitodens 343-F WS4A

Your boiler is most likely asking for its routine annual service, which is a reminder rather than a breakdown, so it should keep working while you arrange a visit from a Gas Safe engineer.

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

Control mode. Cause: Service. Measures: Service the equipment. After the service, set coding address "24:0".

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 343 F Ws4a 5592883 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.

Engineer required

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

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Boiler cover options

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All 59 fault codes on the Vitodens 343-F WS4A

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

9A9b9C9F10182028303840485058929394A6A7b0b1b4b5b7b8bAbCbdbEbFC2CdCECFdAdbdddEE4E5E8E9EAEbECEdF0F1F2F3F4F8F9FAFCFdFEFF

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