High Lockout
Reset neon does not extinguish on Potterton Performa System HE

Your boiler has developed an internal electrical fault that is preventing it from restarting even after you try to reset it.

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

Selector switch or PCB failure (Section K)

What causes this fault?

This fault occurs when the boiler's internal computer or the main control dial fails to communicate correctly, meaning the system cannot clear its memory of a previous error. The most common reason is that the circuits on the main control board have worn out or shorted, preventing the reset signal from reaching the burner.

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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