High Lockout
L6 on Ideal Logic+

Your boiler thinks a flame is present when it should be off, which is a safety lockout preventing the unit from starting.

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 sensors detect a flame after the burner should have switched off. The most common reason is a faulty sensing electrode sending a false signal, or a gas valve that is slightly sticking and allowing a tiny amount of gas to leak through when it shouldn't.

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

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