BoilerFaultCodesWhat the manual says
Manufacturer manualCommunication fault - Vitotrol remote control heating circuit M2. Control mode without remote control
What causes this fault?
This fault occurs when the boiler's main internal computer loses its connection with the remote thermostat or controller managing your second heating circuit. The most common reason is an electrical break in the wiring between the units, a loose connection, or a hardware failure within the communication module itself.
DIY fix possible
Check if the batteries in your wall-mounted thermostat need replacingEnsure the thermostat is within signal range of the boilerTurn the boiler off and back on at the fused spur switch to reset the connection
Avoid the next call-out bill
A cover plan would handle faults like bd: no call-out fees, no surprise bills.
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Related fault codes
All 75 fault codes on the Vitodens 333-F
Seeing a different code? Every code this model can display, in one place.
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