High Lockout
9.1.3 on Ideal HP290

Your boiler has detected that its electrical power wires have been connected in the wrong order, preventing it from starting up safely.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

9.1.5View →

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