High
Lights: On Off Flash on Potterton Promax HE Store

Your boiler is detecting that the electrical wires providing its power have been swapped around, which is 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

Live & Neutral Reversed. Incoming Live and Neutral reversed.

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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