High
95 H......n..... on Ideal Isar System

Your boiler has detected that the electrical supply wires are connected in the wrong order, which is preventing it from starting up 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 ERROR (Check wiring to the boiler for reversed live and neutral)

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 →LFView →

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