I'm noticing spots at the bottom of my kettle—what is this residue?

This is called scaling, which occurs when hard water with high mineral content is boiled in the kettle. The mineral concentration in your water can vary depending on your location.

To minimize this buildup, we recommend regularly cleaning the kettle as detailed in the manual.

Note: Always descale the kettle before and after storing for long periods of time.

How do I clean my kettle?

Note: Do not use steel wool, as this can scratch the kettle.

  1. Unplug the kettle, pour out the water, and allow it to cool.
  2. Squeeze half a lemon or ½ cup of distilled vinegar into the kettle.
  3. If there is thick scaling, you can scrub the kettle’s inner walls with a non-abrasive scrub sponge.
  4. After scrubbing, pour in 2 cups of water and bring the kettle to a boil.
  5. Pour out the mixture then wipe off any remaining scaling with a non-abrasive cloth, sponge, or cleaning brush.

For quick descaling:

  1. Add 3 tablespoons of baking soda + ½ cup of vinegar into the kettle.
  2. Swirl the mixture around until it coats the walls of the kettle.
  3. Wipe the kettle walls with a non-abrasive sponge and pour the mixture out.

This method only works for a thin layer of scaling.

Is there any plastic on the inside of the kettle?

The kettle’s inner chamber does not contain any plastic. The water will only come in contact with metal, glass, and possibly a silicone sealing ring (depending on the model).

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  • Lynn Rudolph

    My Cosori is about 3 months old. The water heats fine. But a brown film develops on the inside of the glass after every couple of uses. I’m concerned after reading a warning on a Cosori box that there might be lead or bpa contamination. The bottom of the kettle is stained continually. 

    Lynn Rudolph
  • Lisa Espinosa

    The Cordori kettle has a lead warning. Where is the lead coming from?

    Lisa Espinosa