High Lockout
All neons flashing on Potterton Performa 28i

Your boiler has detected a system error or internal failure that is preventing it from starting up correctly.

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

If regular resetting is required or appliance still does not operate, investigation is necessary.

What causes this fault?

This fault occurs when the boiler's internal computer, the Printed Circuit Board, suffers an electrical failure or loses communication with its sensors and switches. The most common reason is age-related wear to the board's components or loose connections in the wiring that prevent the boiler from performing its safety checks.

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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