Medium
Vitodens 222-F on Viessmann Vitopend 111

Your boiler is having trouble communicating with its internal controls or sensors, which might cause your heating or hot water to behave unpredictably.

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

Control mode

DIY fix possible

Locate the power switch or fused spur for the boilerTurn the power off for 60 secondsTurn the power back on and wait for the system to reboot

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