BoilerFaultCodesYour boiler has detected an electrical wiring error where the power supply wires are connected incorrectly or there is a serious electrical fault.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Wiring fault Live on neutral connection Correct fault
What causes this fault?
This fault occurs when the boiler detects that the electrical polarity of the power supply is reversed, meaning the live and neutral wires have been swapped. This most commonly happens after recent electrical work in the home or if a component, like the main circuit board, has developed a serious internal short circuit.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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