High
Lockout light on Ideal Concord Super Series 4

Your boiler has failed to start because it cannot detect a flame, meaning you currently have no heating or hot water.

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

Illuminates if the burner fails to light at the end of the 4 second ignition period.

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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