BoilerFaultCodesYour boiler’s internal computer chip has encountered a communication error or is missing, preventing the system from running safely.
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) fault
What causes this fault?
This fault occurs when the boiler's main control board loses its connection with the small plug-in memory chip that tells the unit exactly how to operate. The most common reasons are a loose connection due to vibration, a malfunction within the chip itself, or a hardware failure on the main circuit board that prevents it from reading the chip's data.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like C2 — 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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