BoilerFaultCodesTechnical description
Communication error with control unit
What causes this fault?
This fault occurs when the boiler's internal electronic brain loses its ability to talk to the control panel or the main sensors. It is usually caused by a loose connection in the internal wiring or a critical component failure on the main circuit board. Over time, heat and vibration inside the unit can dry out solder joints or cause plugs to become slightly unseated, breaking the communication loop.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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