BoilerFaultCodesWhat the manual says
Manufacturer manualCommunication fault - Vitotrol remote control heating circuit A1. Control mode without remote control
What causes this fault?
This fault occurs when the boiler's main control board loses the electronic link with your wall-mounted thermostat or remote unit. The most common reason is a loose or broken communication wire, though it can also be caused by a software glitch or a failure in the remote control unit itself.
DIY fix possible
Check that the Vitotrol remote control unit is correctly seated on its wall bracket.Inspect the remote control for any dead batteries if it is a wireless version.Perform a power reset on the boiler to see if communication re-establishes.
Avoid the next call-out bill
A cover plan would handle faults like bC: no call-out fees, no surprise bills.
Affiliate links. We may earn a commission at no extra cost to you.
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.