High
89 H......n..... on Ideal Isar HE

Your boiler is failing to start because the electrical supply wires—specifically the live and neutral—have been connected the wrong way around.

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

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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