BoilerFaultCodesYour boiler has lost its connection with the remote control unit used to manage the heating and is currently operating in a basic backup mode.
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 without remote control - Communication fault-Vitotrol remote control heating circuit A1
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.
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