BoilerFaultCodesTechnical description
Internal control unit error
What causes this fault?
This fault occurs when the boiler's central control board suffers a critical electronic failure or loses the ability to talk to its internal sensors. Most commonly, this is caused by aged electrical components on the circuit board wearing out or a sudden power surge disrupting the unit's delicate memory.
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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