BoilerFaultCodesYour boiler has detected a communication issue or a fault with one of its internal ignition electrodes, meaning it cannot safely light the burner.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Second electrode
What causes this fault?
This fault occurs when the boiler's control system loses contact with the secondary electrode responsible for creating the spark to light the gas. It is usually caused by the electrode becoming worn out, cracked, or covered in carbon deposits, which prevents it from sending the correct electrical signal back to the main circuit board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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