BoilerFaultCodesYour boiler is failing to detect a flame after it tries to ignite, meaning it will not stay lit to provide heat or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: lonisation
What causes this fault?
This fault occurs when the boiler's internal computer cannot confirm that a flame has successfully lit inside the burner. The most common reason is a build-up of carbon or wear on the sensing probe, though it can also be caused by an unstable gas supply or a faulty control board failing to process the signal.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 6 — no call-out fees, no surprises.
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