High Lockout
H......n........ on Ideal Mexico HE

Your boiler has detected that the electrical wiring coming into the unit is connected incorrectly, meaning the live and neutral wires are swapped.

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

PHASE REVERSAL ERROR

What causes this fault?

This fault occurs when the electrical supply to the boiler has been wired with the live and neutral connections swapped. It most commonly happens following recent electrical work in the home or if a new plug or fused spur has been installed incorrectly. The boiler's safety sensors detect this 'reversed polarity' and shut the system down as a precaution to prevent damage to the internal electronics.

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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