Medium Warning
71:1 on Viessmann Vitodens 050-W

Your boiler is switching itself off because it is struggling to reach the correct temperature while trying to heat your hot water tank.

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

OFF during DHW loading to set value 1

What causes this fault?

This fault occurs when the boiler is unable to transfer heat to your hot water tank quickly enough, causing the internal water temperature to climb too high and trigger a safety shutdown. The most common reasons are a faulty sensor giving the boiler incorrect readings or a mechanical failure in the valve that directs hot water to your cylinder.

Engineer required

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

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Related fault codes

F2View →58View →A9View →

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