To descale a kettle, fill it about two-thirds full with one part white vinegar to two parts water, bring it to a boil, and leave it to stand overnight. Pour it out, then boil a full kettle of fresh water and throw it away. Do that rinse twice. If your kettle's manual names a descaler instead of vinegar, use that.
The vinegar method above comes straight from the Breville BKE395 kettle manual. Plenty of kettles are fine with it. Some aren't, which is why the manual is worth thirty seconds before you start.
How often should you descale a kettle?#
Russell Hobbs recommends descaling at least monthly, and that's a good rule if you live somewhere with hard water and use the kettle several times a day.
In practice, let the inside of the kettle set the pace. Look in when you refill it. A faint white haze on the base is fine. A crust you could scrape with a fingernail, or flakes floating in your tea, means it's overdue. Soft-water households might go three months or more between descales; very hard water can need it every two or three weeks.
How to descale a kettle with vinegar#
- Unplug the kettle and let it cool. Empty any water.
- Fill it about two-thirds full with one part white vinegar and two parts water. Stay under the max line.
- Put the kettle back on its base and bring it to a boil.
- Unplug it and leave the solution to stand overnight. Keep the lid closed and put a note on it so nobody makes tea with it.
- In the morning, pour the solution away. If scale is still clinging on, a soft brush or cloth will usually lift it now.
- Fill with fresh water, boil it and pour it away.
- Repeat the fresh-water boil once more. Now it's ready to use.
The kitchen will smell of vinegar while it boils. Open a window. The smell goes once the rinse boils are done, and if you can still taste vinegar, run one more.
When to use a descaler instead#
Some manufacturers specify a commercial descaler. Russell Hobbs' help page says to use only a descaler that's suitable for plastic products and to follow the instructions on the pack. The manual for its 25240 kettle says to descale at least monthly with a proprietary descaler, and warns that kettles returned under guarantee with faults caused by scale will be charged for repair.
So if your manual names a descaler, use it, at the dilution and contact time on its label, and do every rinse it asks for.
Clean the spout filter too#
Many kettles have a mesh filter behind the spout that catches flakes of scale. It clogs, and a clogged filter makes the kettle spit and pour slowly.
On the Russell Hobbs 25240, the filter slides up and out of guides behind the spout. Rinse it under a running tap while brushing it with a soft brush, then slide it back in. Other kettles use clips or a pull-out tab, so check the manual before you pull on anything. While the filter is out, give the spout a look, too.
Are the brown spots in my kettle rust?#
Usually not. Breville's manual says the brown stains that appear on its stainless steel element are mineral deposits, not rust. They come off with the same descaling routine. If you've descaled and the spots are still there and pitted, that's a different story, and it's worth contacting the manufacturer.
What not to do#
- Don't chip scale off with a knife or a metal scourer. You'll scratch the base, and on a kettle with an exposed element you can damage it.
- Don't put the kettle body or the power base in water. The base must stay dry.
- Don't mix descalers, or add vinegar to a commercial descaler.
- Don't leave a descaling solution in an unattended kettle where someone might drink it.
Hard water hits more than the kettle#
If your kettle scales up fast, everything else that heats or sprays water is collecting the same minerals. Your coffee maker needs descaling on a similar schedule, and the crust on a showerhead or a faucet aerator comes off with much the same vinegar soak.
A monthly ChoreLists.com reminder works for most hard-water homes. Note your kettle model and the descaler you use in the task so you're not hunting for the ratio next time.