BoilerFaultCodesYour boiler's internal memory card has developed a communication fault, meaning the control system cannot verify the specific settings for your model.
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 memory chip that stores your appliance's specific tuning profile. The most common reason is that the chip card has vibrated loose, failed electronically, or the main circuit board itself can no longer read the data required to operate safely.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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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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