High Lockout
PCB Fault on Potterton Performa SL HE 9 2

Your boiler has experienced an internal computer failure and has shut down for safety, meaning it will no longer provide 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

Automatic Lockout. Internal PCB failure discovered during self-check.

What causes this fault?

This fault occurs when the boiler's internal control center suffers a critical hardware failure or a short circuit on its circuitry. The most common reasons are electrical surges, general wear and tear of the components over time, or moisture ingress from a slow internal leak that has reached the sensitive electronic board.

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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