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

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.