Sheets, towels, iron
How to Descale a Kettle
20–30 g citric acid per litre, or 1:1 white vinegar, heat, sit 15–30 minutes, rinse twice. Monthly in hard water. The element is not supposed to wear a white crust.
Updated 27 Aug 2026 · 6 min read · how to descale a kettle
Citric is cleaner; vinegar is in the cupboard
Citric acid (20–30 g/L) is odourless, cheap per kilo, and the same acid used in commercial descalers. White vinegar 1:1 works and makes the kitchen smell like a chip shop for an hour. Do not mix either with bleach. Do not use neat brick-cleaner acid unless you like pits in a stainless disc.
Live vinegar in a plastic kettle can linger; extra rinse. Citric is kinder there.
| Water hardness | Interval | Dose |
|---|---|---|
| Hard (you see crust in weeks) | Every 3–4 weeks | 30 g citric / L, or 1:1 vinegar |
| Moderate | Every 6–8 weeks | 20 g citric / L |
| Soft / filtered | 2–3× a year or when visible | 20 g citric / L |
| After a holiday of neglect | Now, maybe twice | Do not chip it with a knife |
Heat, wait, rinse, dummy boil
The sit is what dissolves CaCO₃, not a 20-minute rolling boil that fills the house with vinegar. Empty, rinse the spout filter — it hides a grey paste — then a full plain boil you throw away so the first cup does not taste like salad. The same mild-acid idea lifts tint on stainless pans; it will not fix stuck food, which is heat, not scale.
When scale is a symptom of the lid
If you cannot reach the disc, the kettle was wrong. If the thermostat clicks off early, scale is insulating it — descale before you bin a £40 kettle. Shower heads and kettle discs fail the same way; the shower’s cousin is washing a shower curtain plus a separate descale of the head, not a scented candle.
Questions, answered
- Can I use cola?
- Phosphoric acid will nibble scale and leave sugar. Citric acid is 20 g and does not make a sticky kettle. Use cola as a drink.
- Will descaling void a warranty?
- Not if you use citric or vinegar as the manual allows. Metal spatulas on a concealed element will.
- The kettle still smells of vinegar.
- You skipped the dummy boil. Do two. Next time use citric.
