BoilerFaultCodesYour boiler is failing to detect the flame it has lit, causing the system to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Ionization Lead
What causes this fault?
This fault occurs when the boiler's control system loses the electrical signal used to confirm that a flame is actually present inside the burner. The most common cause is a degraded or dirty sensing electrode that can no longer 'see' the fire, or a faulty wiring lead that is failing to carry that signal back to the main circuit board.
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 E83477 — no call-out fees, no surprises.
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