High Lockout
neon illuminated on Potterton Performa 30 HE

Your boiler has detected a general internal fault and has locked itself out to protect the system.

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

Go to section 'A'

What causes this fault?

This fault occurs when the boiler fails to light or detect a flame after several attempts, leading the system to shut down for safety. The most common reasons include a worn-out ignition spark, a faulty gas valve not releasing fuel, or the main control board failing to process the start-up sequence.

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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