BoilerFaultCodesYour boiler's internal memory chips are having trouble communicating with each other, meaning the control board doesn't recognise the boiler's specific settings.
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 ID (BCC-iD) of internal Electrically Erasable Programmable Read-Only Memory (EEPROM) is inconsistent
What causes this fault?
This fault occurs when the boiler's main control board loses its connection to the memory chip that holds the unit's unique identity and configuration settings. The most common reason is a physical failure of the chip itself or electrical interference that has corrupted the data exchange between internal components.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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