High
Burner lock indicator on Ideal Icos

Your boiler has shut down because the burner failed to light or stay lit, requiring a manual reset to try and fire up again.

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

Feeds signal from lockout terminal on burner control box to lock out indicator on boiler control panel.

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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