While you are using this unit, minerals contained in the water (like calcium) can get stuck on the inner container. This is called "scale", and it is harmless.

－ Milky-white gritty surface (caused by calcium)

－ White or glittering floating material (crystals of minerals)

－ Discoloration in the finish like dark brown, gray, or green areas

(metallic ion made on the fluororesin covering)

These are not discoloration or corrosion of the inner container itself, nor are they flakes from the fluororesin covering.

Put citric acid in the inner container.

1. Amount of citric acid to be used at one time (80 g / 7 level tablespoons)

2. Add water to the maximum water level mark, and

mix the citric acid and water well.

3. Close the lid and boil the water.

4. Remove the lid and drain away the hot water.

5. Refill with water and boil it to remove the smell of the citric acid.

6. Drain the hot water away in the same way as 4.

* Since the citric acid used for cleaning is a food additive, it is harmless to humans.

The cause of this is “scale”, and it is harmless.

* Water with a large content of minerals in it such as mineral water or ionised water, is more likely to cause a scale or white layer in the hot water.