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Cut one lemon or lime to small slices

Put the slices into the kettle , add water and boil

Once boiled, allow the kettle to cool and then reboil. Repeat this twice

Dispose of the water through the sink or on your plant

Now bring the kettle to a boil with plain water. As before, let the water cool and then repeat twice. This is to remove the smell (and possibly taste) of the citrus in your kettle.

Once you've done this, dispose of the water mindfully and your kettle is clean and ready to use!