BoilerFaultCodesYour boiler's internal computer chip has lost connection or failed to communicate with the main control board, preventing the system from starting.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler chip card (BCC) activation fault
What causes this fault?
This fault occurs when the main control board can no longer read the data from the small plug-in chip that tells the boiler exactly how to operate. The most common reason is that the chip has vibrated loose, or the electronic connection between the chip and the board has failed due to age or a power surge.
DIY fix possible
Turn the boiler power off at the fused spur switchWait for 30 secondsTurn the power back on and press the 'Reset' button
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A boiler cover plan would cover faults like C0 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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