BoilerFaultCodes.com
No neon illuminated High Lockout

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

Call an engineer soon

Book a Gas Safe engineer within 24–48 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.

Typical repair cost £80-250 (including labour)

DIY fix possible

Check if the boiler's power switch is turned onCheck your home's main fuse box/consumer unit to see if a circuit has trippedCheck the fuse in the spurred power socket next to the boiler

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