Technical description
Control mode without remote control: Communication fault - Vitotrol remote control heating circuit M2
What causes this fault?
This fault occurs when the boiler's main control board loses its digital handshake with the remote thermostat managing your second heating zone. Most often, this is caused by a loose connection in the low-voltage wiring or a hardware failure within the Vitotrol unit itself.
DIY fix possible
Check if the Vitotrol remote unit is properly seated on its wall baseSwitch the boiler off at the fused spur, wait 30 seconds, and switch it back on to reset the connectionInspect the remote unit batteries (if applicable) or check for visible damage to the wiring leading to the unit