BoilerFaultCodesYour boiler has detected an internal safety electronic error and has stopped working to prevent a malfunction.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Ionisation oscillator test
What causes this fault?
This fault occurs when the boiler's internal computer fails a critical self-test regarding the flame detection circuitry. It is usually caused by a hardware failure within the main control board or a communication error in the internal wiring, meaning the boiler can no longer safely monitor the burner. Because the system cannot guarantee it is detecting the flame correctly, it shuts down as a safety precaution.
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 T6 — no call-out fees, no surprises.
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