High
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.

What the manual says

Manufacturer manual

Boiler lockout due to 5 restart attempts within 15 minutes

From this model's manual
Verified against the Ideal Logic Combi Esp1 installation & service manual, page 55.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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