BoilerFaultCodesTechnical description
Internal control unit error
What causes this fault?
This fault occurs when the boiler's central brain, the Printed Circuit Board, can no longer send or receive signals correctly throughout the system. The most common reason is a physical failure of the electronic components on the board or a loose connection in the wiring harness that links the controls together.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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