High Lockout
E1 on Ideal HP290

Your boiler has detected that the electrical wiring coming from your home’s power supply matches the wrong terminals, meaning the power flow is backwards.

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 boiler detects that the live and neutral electrical connections have been swapped at the power source or within the internal wiring. It is most commonly caused by recent electrical work in the home or an incorrectly wired plug or fused spur, which poses a safety risk to the internal electronics. Because British boilers are polarity-sensitive, the system will prevent operation until the wiring is physically corrected.

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

E2View →

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