BoilerFaultCodesYour boiler's computer brain has suffered a serious internal electronic failure and can no longer communicate with the heating system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal failure control panel or defective ModuLine.
What causes this fault?
This fault occurs when the boiler's internal computer experiences a critical electronic crash or a hardware failure within its circuitry. It is usually caused by the degradation of sensitive electrical components over time or a sudden power surge that damages the communication links on the control board. When this happens, the brain of the boiler can no longer send instructions to the burner or pump, leading to a total system shutdown.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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