High Lockout
95 H......n..... on Ideal Esprit HE

Your boiler has detected that the electrical wiring coming into the unit is connected backwards, which is preventing it from starting up for safety reasons.

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 (Check wiring to the boiler for reversed live and neutral)

What causes this fault?

This fault occurs when the electrical supply to the boiler has been wired incorrectly, causing the live and neutral connections to be swapped. It most commonly happens after electrical work has been carried out in the home or if a new power cable has been fitted to the boiler. For safety, the boiler will refuse to ignite because it cannot correctly verify that the electrical circuit is safe to operate.

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

L9View →H9View →

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