BoilerFaultCodesYour boiler's internal computer has encountered a critical error or is having trouble communicating with its electronic security card, 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: Burner in fault position. Control unit fault or wrong coding card. Check the coding card and replace if necessary, or replace the control unit.
What causes this fault?
This fault occurs when the boiler's main control board loses its connection with the small electronic chip that tells it how to operate safely. It is usually caused by electrical interference, a loose chip connection, or a physical failure within the central circuit board itself. Because the boiler no longer knows its own safety parameters, it shuts down immediately to prevent damage.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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