Medium Warning
56:0 on Viessmann Vitodens 200-W

Your boiler is experiencing an issue where it cannot properly monitor or control the temperature of your hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

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.

Engineer required

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

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Related fault codes

A7View →

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