BoilerFaultCodesTechnical description
Control box fault
What causes this fault?
This fault occurs when the boiler's main control board experiences an internal electronic failure or a loss of data. It is often caused by a component failure on the circuit board itself or a loose connection in the internal wiring preventing the computer from sending instructions to the burner. In some cases, an external power surge or moisture ingress can also damage the sensitive electronics inside.
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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