High
IGNITION LOCKOUT INDICATOR on Halstead Best 20

Your boiler has stopped working because it failed to light the flame, which usually happens due to a blocked flue, a frozen pipe, or a gas supply issue.

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

Neon illuminates if the boiler fails to light; wait 15 seconds and reset the ignition by depressing the reset button once.

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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