High
On On On on Potterton Suprima HE

Your boiler has lost its internal electrical connection, meaning it cannot receive the signals needed to operate and will currently have no heating or hot water.

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

LV Wiring Harness. Ensure 8-way PCB connector securely pushed in. If fault persists replace LV wiring harness.

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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