High Lockout
LC on Ideal Logic Combi ESP1

Your boiler is repeatedly failing to start and has locked itself out for safety after five unsuccessful attempts in a short period.

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

Restart occurs 5 times within 15 minutes.

What causes this fault?

This fault occurs when the boiler senses a repeated failure to maintain a stable flame, causing it to shut down for safety after five unsuccessful ignition attempts. It is usually caused by a component failing to detect the flame correctly or an inconsistent supply of gas reaching the burner. Because the system cannot verify it is burning fuel safely, it stops operating to prevent unburnt gas from building up.

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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Related fault codes

L2View →F2View →L1View →

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