How To Descale a Coffee Maker | Kitchn
Sep 22, 2017· If your machine has a light indicator, then the light will turn on to let you know when the machine needs descaling. If you have an older machine or a model with less bells and whistles, it might not. You don''t even need a light, though, because you''ll usually be able to see when it''s time — there will be a chalky white residue.