High Lockout
L06 on Ideal Logic Max System

Your boiler is detecting a flame even though the gas valve should be closed, which is a safety precaution that stops the boiler from running.

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

Flame On Before Gas Valve On

What causes this fault?

This fault occurs when the boiler's internal sensors detect a flame while the system is in a standby state and the gas valve should be shut. It is often caused by a faulty sensor sending a false signal, a leaking gas valve that is letting fuel through when it shouldn't, or a moisture-damaged control board misinterpreting electrical signals.

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

F2View →L2View →LCView →

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