BoilerFaultCodes.com
UA-66 High

Your boiler's internal memory chips are having trouble communicating with each other, meaning the control board doesn't recognise the boiler's specific settings.

Technical description: Boiler chip card ID (BCC-iD) of internal Electrically Erasable Programmable Read-Only Memory (EEPROM) is inconsistent
Typical repair cost: £180-450 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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