BoilerFaultCodesIdeal L06 Fault Code
The Ideal L06 fault code means: 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.. It appears on 3 Ideal models in our database.
Technical description: Flame On Before Gas Valve On
What causes the Ideal L06 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Ideal models that show the L06 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ideal L06 fault code information on this page is sourced and cross-checked against the official Ideal service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026