High Lockout
L6 on Ideal Logic Combi ESP1

Your boiler thinks it sees a flame when there shouldn't be one, so it has shut down as a safety precaution.

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

False Flame Lockout

What causes this fault?

This fault occurs when the boiler's internal sensor detects a flame signal even though the gas valve should be closed and the burner turned off. The most common reason is a faulty sensing electrode that is sending a false signal, or a failing control board that is misinterpreting electrical interference as a live flame.

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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