High
Ignition Lock-out neon on Halstead Best 80

Your boiler has stopped working because it failed to light the flame properly, so it has shut itself down for safety.

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.

What the manual says

Manufacturer manual

Boiler has failed to ignite. Turn thermostat to maximum and ensure programmer is switched on before pressing reset button.

From this model's manual
Verified against the BEST20db20Inst20Manual installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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