Technical description
Internal control box error (flame circuit fault)
What causes this fault?
This fault occurs when the boiler's main control board fails to correctly process the signals required to manage and monitor the burner's flame. The most common reason is a physical failure of the internal electronics on the circuit board, though it can also be triggered by worn-out ignition parts or damaged wiring that disrupts the signal flow.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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