High
H n on Ideal Classic FF 330

Your boiler has detected that the electrical supply connections are wired in the wrong way round, preventing it from starting 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 - 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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