BoilerFaultCodesYour boiler is receiving power from the mains supply and is ready to operate.
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 status indicator showing that your boiler has a healthy electrical connection to the mains power supply. It confirms that the internal control system is energized and the unit is waiting for your thermostat or programmer to call for heating or hot water. If your heating isn't working while this light is on, the issue likely lies with your external controls rather than the boiler itself.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
Find a Gas Safe engineer
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