BoilerFaultCodesYour boiler has detected that the electrical wiring coming into the unit is connected backwards, which is a safety risk that prevents it from starting up.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Live & Neutral Reversed. Incoming Live and Neutral reversed.
What causes this fault?
This fault occurs when the electrical supply wires are connected to the wrong terminals, meaning the 'live' and 'neutral' paths are swapped. It often happens after recent electrical work, such as a new socket being installed or a replacement fused spur switch being wired incorrectly. The boiler prevents itself from firing up as a safety precaution because operating with reversed polarity can make the internal components live even when the power appears to be off.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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