High
90 H......n........ on Ideal Isar M30 / M100

Your boiler's electrical power supply has been connected with the live and neutral wires swapped, which is preventing the system from detecting the flame 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

PHASE REVERSAL

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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