Technical description
Internal control box failure (parameters): check parameters and reset.
What causes this fault?
This fault occurs when the boiler's main control board loses its memory or fails to read the specific identity chip that tells it how to operate. This is usually caused by an electrical component failure on the circuit board or a loose connection to the parameter plug. Essentially, the boiler has forgotten its own identity and refuses to fire for safety reasons.
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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