High Lockout
4.6 on Ideal Vogue Combi

Your boiler thinks it sees a flame before it has even started the ignition process, which is a safety conflict that prevents it 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 signal even though the gas valve hasn't been told to open yet. The most common reasons are a damaged flame sensing electrode that is sending a false signal, a gas valve that is leaking slightly, or a glitch in the main circuit board's electrical logic.

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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