High Lockout
No neon illuminated on Potterton Performa 24

Your boiler has no power and the control panel lights are completely switched off.

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’: Check 230V at main terminals L and N, main terminal fuse, and selector terminals.

What causes this fault?

This fault occurs when the electrical supply to the boiler's internal components is interrupted, meaning the control board cannot receive any power. The most common reasons are a blown internal glass fuse caused by a component short-circuiting, a faulty main circuit board, or a failure in the power selector switch. Essentially, the 'brain' of the boiler has lost its electricity and cannot tell the system to start up.

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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