BoilerFaultCodesThis light simply indicates that there is power reaching the boiler and it is switched on.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Mains electricity ON
What causes this fault?
This is not actually a fault, but a confirmation that your boiler is receiving electrical power from the main supply. It indicates that the internal circuitry is live and the appliance is ready to start the ignition process once there is a demand for heating or hot water. If this light is off, it usually means there is a tripped fuse, a blown internal fuse, or the isolation switch has been turned off.
DIY fix possible
Check that the boiler power switch is onEnsure no other fault lights are flashingMonitor the boiler for normal operation
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