Low Warning
56:0 on Viessmann Vitodens 300-W

Your boiler is experiencing a communication issue with its internal hot water controls, which may limit the temperature settings available to you.

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

DHW temperature adjustable from 10 to 60°C

What causes this fault?

This fault occurs when the boiler's control system loses the signal from the probe that monitors your hot water tank. The most common reason is that the internal sensor has developed a electrical fault or the wiring connecting it to the main circuit board has become loose or damaged. Without this data, the boiler cannot safely determine how much heat is needed for your taps and showers.

DIY fix possible

Turn the boiler power off at the main fused spur switchWait 60 secondsTurn the power back on and see if the code clears

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Related fault codes

58:0View →B0View →

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