Low
0F on Viessmann Vitodens 300-W

Your boiler is currently set to maintenance mode, which usually means it is undergoing a service check or the service settings weren't exited correctly.

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: Maintenance

From this model's manual
Verified against the Viessmann/Viessmann Vitodens 200 W 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 if a heating engineer has recently worked on the unit and left it in service mode.Try to exit the service/maintenance menu using the boiler control panel 'back' or 'OK' buttons.Perform a simple reset of the boiler to see if it clears the status notification.

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Related fault codes

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All 60 fault codes on the Vitodens 300-W

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

9A9b9C9F101820283038404850515858:05980:092939497:2A2:0A7b0b1b4b5b7b8bAbCbdbEbFC2C5C6C7CdCECFdAdbdEE4E5E6F0F1F2F3F4F7F8F9FAFdFE

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