Low Information
6F:0 to 6F:100 on Viessmann Vitodens 200-W

Your boiler is providing an advisory notification about how much power it is using to heat your hot water, rather than indicating a mechanical 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.

Engineer required

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

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