Low Information
6F:0 to 6F:100 on Viessmann Vitodens 300-W

Your boiler is providing an informational update about the maximum power level it is using to heat your hot water, rather than reporting a functional breakdown.

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.

Technical description

Max. output during DHW loading adjustable from 0 to 100%

What causes this fault?

This notification occurs when the boiler is informing you that the maximum power output dedicated to heating your hot water has been manually adjusted or restricted. It is not a mechanical failure, but rather a configuration setting that tells the system how hard the burner should work when refilling your hot water cylinder. The most common reason for seeing this is following a recent service or setup change where the engineer has optimized the unit for energy efficiency.

DIY fix possible

No action is required as this is an advisory message indicating the power output setting.If hot water is too slow to heat, contact a professional to adjust the maximum output via the control unit.Restart the boiler to see if the notification clears from the display.

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Related fault codes

6F:100View →

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