BoilerFaultCodesYour boiler’s internal computer has encountered a software or hardware error and can no longer communicate with the rest of the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System fault boiler electronics / basic controller
What causes this fault?
This fault occurs when the boiler's main control board experiences a critical internal communication failure, essentially meaning the 'brain' of the unit has become unresponsive. The most common reason is an electrical component failure on the printed circuit board or a loose connection within the internal wiring harness that prevents data from traveling between the sensors and the controller.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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