BoilerFaultCodesYour boiler’s internal computer has encountered a communication error or internal glitch that is preventing it from running properly.
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 loses its ability to communicate with other internal electronic components. It is typically caused by a data error within the software or a physical failure of the circuitry that manages the boiler's core operations. Think of it as a computer crash where the hardware can no longer process the instructions needed to keep the system running safely.
DIY fix possible
Locate the Reset button on the front control panelPress and hold the Reset button for three seconds until the boiler restartsWait up to 10 minutes for the boiler to complete its startup sequence
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