High Lockout
L6 on Ideal Logic+ System

Your boiler thinks it sees a flame even though it isn't currently firing, causing it to 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 at a time when the burner should be off. The most common reason is a faulty sensing electrode that is sending an incorrect electrical signal to the main control board, or moisture buildup on the electrical components causing a short circuit.

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 →LCView →

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