Medium Warning
be on Viessmann Vitodens 222-W

Your boiler is having trouble communicating with the wall-mounted thermostat control because of a setup or configuration error.

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: Vitotrol remote control incorrectly encoded

What causes this fault?

This fault occurs when there is a mismatch between the boiler's settings and the physical remote control device installed on your wall. It essentially means the boiler is looking for a specific type of controller that it cannot find or recognize, often due to an incorrect configuration code being entered into the system. In some cases, a loose connection or damaged wiring between the boiler and the thermostat can also trigger this communication failure.

Engineer required

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

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Related fault codes

b0View →b1View →b5View →

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