BoilerFaultCodesTechnical description
Control box failure
What causes this fault?
This fault occurs when the boiler's internal computer chips or electrical circuits suffer a terminal failure, often due to age, overheating, or moisture ingress. Over time, the solder joints and components on the circuit board can degrade, making it impossible for the system to process signals or safely manage the burner.
This failure is more common during the autumn months when the boiler is switched back on after a summer of inactivity, as electrical components can fail under the sudden stress of constant use.
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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