Emergency Lockout
Flame On Before Gas On on Ideal Logic Max Combi

Your boiler's safety sensor detects a flame before the gas valve has even been told to open, which usually means a internal component is stuck or sending a false signal.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

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What causes this fault?

This fault occurs when the boiler's control system senses a flame signal at a time when there should not be any fire present in the burner. The most common reason is an internal electronic failure where the sensing probe sends a false signal, or the gas valve has failed to close properly and is leaking fuel into the combustion chamber.

Engineer required

This is a emergency 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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