BoilerFaultCodesYour boiler has detected that its electrical power wires have been connected in the wrong order, preventing it from starting up safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Live and Neutral reversed
What causes this fault?
This fault occurs when the electrical supply to the boiler has been wired incorrectly, meaning the 'live' and 'neutral' power connections are swapped. This often happens after recent electrical work in the home or if a new plug or fused spur was installed without checking the correct polarities. To ensure your safety, the boiler's internal computer detects this error and prevents the system from firing up.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 9.1.3 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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