High
Lights: On On On on Potterton Suprima HE

Your boiler has lost the internal connection needed to communicate with its control system, causing it to stop heating.

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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