BoilerFaultCodesYour boiler has detected that the electrical wiring coming into the unit is connected the wrong way round.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Supply L and N are reversed
What causes this fault?
This fault occurs when the live and neutral electrical connections are swapped, meaning the power is flowing into the boiler through the wrong wire. It typically happens after recent electrical work has been carried out near the boiler, or if a new fused spur was installed incorrectly. Because this is a safety risk, the boiler's control board will automatically stop the unit from firing until the wiring is corrected.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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