BoilerFaultCodesYour boiler has shut down completely due to a loss of electrical power or a safety lockout triggered by an internal fault.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Appliance lockout and power failure
What causes this fault?
This fault occurs when the boiler's control system detects a complete interruption in electrical supply or a critical communication failure between internal components. It often happens because a fuse has blown on the main circuit board or because the board itself can no longer process power correctly. In some cases, loose wiring or a sudden power surge can trigger this emergency shutdown to protect the appliance from electrical damage.
DIY fix possible
Check if your main electrical consumer unit (fuse box) has any tripped switches.Ensure the boiler's power isolation switch is turned on.If power is present, try to reset the boiler using the control knob or reset button.
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