BoilerFaultCodesTechnical description
System fault boiler electronics / basic controller
What causes this fault?
This fault occurs when the boiler's two main 'brains'—the primary control board and the display board—stop talking to each other. It is usually caused by a loose internal connection, a glitch in the software, or a component failure on one of the electronic circuit boards. Think of it like a computer crashing because two internal parts can no longer share information.
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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