BoilerFaultCodesYour boiler is detecting a flame even though the gas valve should be closed, which is a safety precaution that stops the boiler from running.
Book a Gas Safe engineer within 24–48 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like L06 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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