BoilerFaultCodesTechnical description
Bunner controller has internal fault
What causes this fault?
This fault occurs when the main electronic brain of the boiler suffers a critical hardware failure or a memory error. The most common reason is age-related wear on the electrical components within the control board, preventing it from safely managing the ignition sequence. Because the boiler can no longer verify its own safety checks, it shut downs completely to prevent any accidents.
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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