Maintenance procedure · Written to ASD-STE100 Issue 9 · Formatted to ANSI Z535

Kettle Descaling

Electric and stovetop kettles — finding out what your own manufacturer permits before you pour anything in, and why the vinegar ratio you found online belongs to somebody else's kettle
ApplicabilityDomestic kettles that heat water — electric jug kettles, variable-temperature electric kettles and stovetop kettles
Task time1 hr 3 min to 10 hr 43 min editorial estimate, not a measurement
PersonnelOne
Revisionv1 · 2026-07-29
BEFORE YOU BEGIN

Before you begin. This procedure is general reference information, not professional advice. Equipment varies by manufacturer, model, and year. Always follow the documentation supplied with your equipment — where it differs from this page, follow the manufacturer. Verify that you have the tools, the working conditions, and the ability to do this task safely. If anything is unclear, if the equipment is damaged, or if the task exceeds your experience, stop and use a qualified professional. You are responsible for your own safety and for the outcome. This site accepts no liability for any loss, damage, or injury arising from the use of this information.

Specifications marked unverified could not be traced to a manufacturer source. Do not rely on them — obtain the value from your equipment documentation.

Summary

Limescale is the chalky white crust that grows on the bottom of a kettle in a hard water area. It slows the boil, raises the energy the kettle uses, and eventually flakes into the tea. Getting it out is easy and cheap: an acid dissolves it, and the acid is usually white vinegar or a shop-bought descaler. Most of the hour this takes is waiting.

The hard part is not the method, it is the number. Search for a kettle vinegar ratio and you will find one, confidently stated, with no kettle attached to it. We read what five manufacturers actually publish, and they do not agree — not on the strength of the solution, and not even on whether you are allowed to boil it. Breville and Fellow boil the vinegar, De'Longhi tells you to catch the switch just before the boil, and Smeg boils plain water first and adds the vinegar afterwards so that it never boils at all. Dualit names a proprietary descaler and no home remedy, while De'Longhi warns that a proprietary descaler can mark the finish of a kettle.

This page prints none of those as a house figure, because there is no house figure to print. It tells you which questions to take to your own documentation, and what each of the five manufacturers actually said.

Safety

WARNING

DO NOT PUT THE KETTLE BASE, THE POWER BASE OR THE POWER CORD IN WATER.
Water in these parts can cause an electric shock.

Necessary equipment

ItemNote
Measuring jugA jug shows the quantity of water that your documentation gives.
Soft clothUse a soft cloth on the outside of the kettle.
Soft brush optionalA soft brush cleans the limescale filter.
Descaling agent materialOnly the agent in the documentation for your kettle is correct.
Clean water materialWater with less mineral content makes less limescale.

Find the correct descaling agent

Estimated 7 min

NOTEThe manufacturers do not agree about the agent or about the quantity. Use the instruction for your own kettle.
Descaling agent chemical compatibility
Unverified — do not rely on this value
CONSULT THE MANUFACTURER DOCUMENTATION FOR YOUR KETTLE BEFORE YOU SELECT A DESCALING AGENT

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

Five tier-1 manufacturer sources give five different answers, and two of them point in opposite directions. Smeg (smeg-kettle-maintenance, accessed 2026-07-29) says the kettle may be descaled with either white vinegar or a specific descaling product. Breville (breville-bke595-kettle-manual, accessed 2026-07-29) names its own Breville Kettle Cleaner (BKC250) or a proprietary kettle descaler, and gives a vinegar method as an alternative. De'Longhi (delonghi-descale-kettle-faq, accessed 2026-07-29) gives white vinegar as the method and adds that care should be taken with proprietary kettle descaler because it could damage the surface finish of the kettle. Dualit (dualit-limescale-guidance, accessed 2026-07-29) names a proprietary descaler for its kettles, names no home remedy at all, and says any other descaling solution must be suitable for the appliance. Fellow (fellow-kettle-descaling-guidance, accessed 2026-07-29) says vinegar and citric acid are both safe and effective and prefers citric acid because it is stronger and leaves no lingering scent. So the proprietary descaler that one manufacturer recommends is the one another manufacturer warns about, and this page does not choose between them. Use the agent named in the documentation for your own kettle.
  1. Read the documentation for your kettle.
    • The documentation names the descaling agent for your kettle.
    • The documentation gives the quantity, the heat instruction and the interval.
    3m
NOTICE

READ THE DOCUMENTATION BEFORE YOU SELECT A DESCALING AGENT.
An incorrect agent can cause damage to your kettle.

  1. Find the descaling agent that the manufacturer of your kettle names.
    • Breville says that its own kettle cleaner or white vinegar is correct.
    • De'Longhi says that white vinegar is correct.
    • Smeg says that white vinegar or a descaling agent from a shop is correct.
    • Dualit gives a descaling agent from a shop and no home agent.
    • Fellow says that white vinegar or citric acid is correct.
    • Use the agent for your own kettle only.
    3m
WARNING

KEEP THE DESCALING AGENT AWAY FROM CHILDREN AND ANIMALS.
The agent is an acid and can cause an injury.

  1. Get the correct descaling agent.
    1m

Prepare the kettle

Estimated 1 min

  1. Empty the water from the kettle.
    <1m
  2. If your kettle has a limescale filter, remove the filter.
    • The limescale filter is usually in the spout of the kettle.
    <1m
  3. Put the kettle on a dry and level counter.
    <1m

Do the descale

Estimated 40 min to 10 hr 15 min

Descaling agent quantity and dilution
Unverified — do not rely on this value
CONSULT THE MANUFACTURER DOCUMENTATION FOR THE QUANTITY AND THE DILUTION

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

The published vinegar strengths are not interchangeable and not close to each other. Breville (breville-bke595-kettle-manual, accessed 2026-07-29) fills the BKE595 to two thirds with one part vinegar to two parts water. De'Longhi (delonghi-descale-kettle-faq, accessed 2026-07-29) also gives one part white vinegar to two parts water. Fellow (fellow-kettle-descaling-guidance, accessed 2026-07-29) gives half vinegar and half water, which is roughly half again as strong. Smeg (smeg-kettle-maintenance, accessed 2026-07-29) gives a quantity rather than a ratio and it is a different shape of instruction entirely: 1 L of water for a KLF03 or KLF04 and 0.5 L for a KLF05, then between 100 and 500 ml of vinegar for the first pair or between 100 and 200 ml for the second, chosen by how much scale is present. Breville's own product is dosed differently again, at 125 ml of Breville Kettle Cleaner to 2 litres of water. Every one of those figures is attached to a named kettle and none of them is a general rule, so this page publishes no quantity of its own.
Descale solution temperature limit
Unverified — do not rely on this value
CONSULT THE MANUFACTURER DOCUMENTATION BEFORE YOU HEAT THE SOLUTION

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

This is the disagreement most readers never find out about, because the ratio is what gets copied around and the heating instruction is what gets dropped. Breville (breville-bke595-kettle-manual, accessed 2026-07-29) boils the vinegar solution and then leaves it overnight. Fellow (fellow-kettle-descaling-guidance, accessed 2026-07-29) also brings the mixture to a boil. De'Longhi (delonghi-descale-kettle-faq, accessed 2026-07-29) does the opposite and tells the reader to switch the kettle off just before the boiling point. Smeg (smeg-kettle-maintenance, accessed 2026-07-29) avoids the question by boiling plain water first and adding the vinegar to the hot water immediately afterwards, so the vinegar is never boiled. Boiling an acid in a kettle is not a detail that can be averaged with not boiling it, and the right answer is a property of your kettle rather than of the method.
Minimum and maximum fill capacity
Unverified — do not rely on this value
READ THE MINIMUM AND MAXIMUM MARKS ON YOUR OWN KETTLE

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

  1. Read the heat instruction in the documentation for your kettle.
    • Breville boils the vinegar solution.
    • Fellow also boils the vinegar solution.
    • De'Longhi stops the kettle before the water boils.
    • Smeg boils the water first and adds the vinegar after the boil.
    • These four instructions are not the same.
    2m
  2. Fill the kettle with water to the level that your documentation gives.
    • Do not fill the kettle above its maximum mark.
    1m
  3. Add the descaling agent at the time that your documentation gives.
    • Breville adds the vinegar to the cold water.
    • Smeg adds the vinegar to the hot water after the boil.
    • The quantity is different for each kettle and for each agent.
    1m
WARNING

DO NOT OPEN THE LID WHEN THE KETTLE IS ON.
Steam and hot water can burn your skin.

  1. Obey the heat instruction in your documentation.
    • Do not use the heat instruction from a different kettle.
    5m
NOTICE

DO NOT KEEP THE SOLUTION IN THE KETTLE FOR MORE TIME THAN YOUR DOCUMENTATION GIVES.
The acid can cause damage to the kettle.

  1. Let the solution stay in the kettle for the time that your documentation gives.
    • Fellow gives a minimum of 30 minutes.
    • Breville gives one night.
    • Smeg gives 8 to 10 hours.
    • De'Longhi gives a time that changes with the quantity of limescale.
    30m
WARNING

LET THE KETTLE BECOME COOL BEFORE YOU EMPTY THE SOLUTION.
Hot liquid can burn your skin.

  1. Empty the solution from the kettle.
    1m

Rinse the kettle

Estimated 11 min to 16 min

  1. Rinse the inside of the kettle with clean water.
    1m
  2. Fill the kettle with clean water.
    <1m
  3. Boil the water.
    4m
  4. Discard the water.
    <1m
NOTICE

DO THE RINSE CYCLE AGAIN UNTIL THE WATER HAS NO SMELL OF THE AGENT.
Some agent stays in the kettle and gives a bad taste to the first drink.

  1. Do the rinse cycle again.
    • Smeg gives a minimum of two rinse cycles.
    • De'Longhi gives two rinse cycles.
    • Continue until the water has no smell of the agent.
    5m

Complete the work

Estimated 4 min

Descaling interval
Unverified — do not rely on this value
CONSULT THE MANUFACTURER DOCUMENTATION FOR THE DESCALING INTERVAL

No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.

Two kinds of answer are published, and they are not the same kind. De'Longhi (delonghi-descale-kettle-faq, accessed 2026-07-29) and Fellow (fellow-kettle-descaling-guidance, accessed 2026-07-29) both give a calendar keyed to water hardness: monthly in a hard water area, and every three months (De'Longhi) or every two to three months (Fellow) in a soft water area. Dualit (dualit-limescale-guidance, accessed 2026-07-29) gives a flat rule of thumb of at least once per month, more or less depending on where the reader lives. Smeg (smeg-kettle-maintenance, accessed 2026-07-29) gives no calendar at all and makes it conditional instead: descale whenever scale appears on the base of the kettle, which the reader is told to inspect periodically. A calendar and a condition are different instruments and averaging them would produce neither.
  1. If you removed the limescale filter, clean the filter with water.
    • A soft brush removes the limescale from the mesh.
    1m
  2. Install the limescale filter in the kettle.
    <1m
NOTICE

DO NOT USE AN ABRASIVE MATERIAL ON THE KETTLE.
An abrasive material can cause damage to the kettle.

  1. Clean the outside of the kettle with a damp soft cloth.
    2m
  2. Record the date of the descale.
    • A record of the date shows when the next descale is due.
    1m

Terminology

This page uses one term for each item and holds it throughout, as ASD-STE100 requires. Equipment sellers and other guides use the names below for the same parts.

limescale
Also called: scale, lime scale, calcium buildup, hard water deposits, the white stuff in my kettle, the white crust, chalky bits, kettle fur, furring up, mineral buildup
descaling
Also called: descale, de-scale, decalcify, delime, clean my kettle, get the limescale out of my kettle, limescale removal
descaling agent
Also called: descaler, kettle cleaner, descaling solution, white vinegar, citric acid, lemon juice, kettle descaler
limescale filter
Also called: kettle filter, spout filter, mesh filter, the little mesh thing in the spout, scale filter
element
Also called: heating element, concealed element, the plate in the bottom, the disc at the bottom of the kettle
kettle
Also called: electric kettle, jug kettle, tea kettle, hot water kettle, electric tea pot, water boiler

When to use a professional

Do not use a descaling agent that the documentation for your kettle does not name. De'Longhi gives a warning that a proprietary descaler can cause damage to the finish of a kettle.

Stop if water comes through the body of the kettle or through the base. Disconnect the kettle from the power supply. Speak to the manufacturer.

Stop if the kettle does not stop after the water boils. Disconnect the kettle from the power supply. This fault is not a limescale fault. Speak to the manufacturer.

Do not open the body of the kettle. Do not do work on the element in the base. Only a qualified technician must do work in a kettle.

Common questions

Can I use vinegar to descale my kettle?

Four of the five manufacturers we read say yes, and the fifth simply does not mention it. Smeg, De'Longhi, Breville and Fellow all publish a white vinegar method for their own kettles. Dualit publishes no home remedy at all and points you at a proprietary descaler instead, telling you that whatever solution you choose must be suitable for the appliance. So vinegar is not the forbidden thing the internet sometimes makes it out to be, but it is also not universally blessed. The one thing none of them says is that a ratio from another brand's kettle is safe in yours.

How much vinegar do I put in a kettle?

There is no general answer and this page deliberately prints no figure of its own. Breville and De'Longhi both give one part vinegar to two parts water. Fellow gives half and half, which is noticeably stronger. Smeg does not give a ratio at all: it gives a litre of water in a KLF03 or KLF04 and then somewhere between 100 and 500 ml of vinegar depending on how much scale there is. Those are four different strengths for four different kettles, so the honest instruction is to read your own manual rather than to copy a number off a page like this one.

Should I boil the vinegar in the kettle or not?

This is the part that usually gets lost when the ratio is copied around, and it is the one where the manufacturers flatly contradict each other. Breville boils the vinegar solution and then leaves it standing overnight, and Fellow also brings the mixture to a boil. De'Longhi says the opposite, telling you to switch off just before the boiling point. Smeg sidesteps it entirely by boiling plain water first and adding the vinegar to the hot water afterwards, so the vinegar never boils. Boiling an acid and not boiling it are not two versions of the same instruction, and we are not going to split the difference for you.

How often should I descale my kettle?

It depends on your water, and the manufacturers answer in two different ways. De'Longhi and Fellow both give a calendar: about monthly in a hard water area, and every two to three months where the water is soft. Dualit gives a rule of thumb of at least once a month. Smeg gives no calendar and tells you to look at the base of the kettle instead and descale whenever scale appears there. If you are in a hard water area the visual test is the more honest one, because your water does not care what month it is.

What is the white stuff in the bottom of my kettle, and is it bad for me?

It is limescale — calcium and magnesium that were dissolved in your water supply and got left behind when the water boiled off. Dualit states plainly that limescale builds up naturally and is harmless to drink, so the flakes in your tea are unpleasant rather than dangerous. The damage it does is to the kettle: Dualit describes deposits blocking working parts and preventing efficient heating, which is why a scaled kettle takes longer and uses more energy. That is the reason to remove it, not your health.

There is a brown stain on the metal disc at the bottom. Is my kettle rusting?

Breville addresses this directly for its own kettles: it states that the concealed element in the base is stainless steel and that brown staining is mineral deposit rather than rust. That is a statement about a Breville kettle and we are not going to extend it to every kettle ever made, but discolouration on a stainless base is far more often scale and mineral staining than corrosion. Descaling normally shifts it. If it does not, and the metal is pitted or flaking rather than stained, that is worth a call to the manufacturer.

Do I have to buy the descaler my kettle brand sells?

Not necessarily, but read your own documentation before you decide, because the manufacturers genuinely disagree here. Dualit recommends a specific proprietary descaler for its kettles and says any alternative must be suitable for the appliance. Breville names its own kettle cleaner or a proprietary descaler from a shop. De'Longhi points the other way and warns that care should be taken with proprietary kettle descaler because it could damage the surface finish. If your kettle has a painted, matt or metallic finish, that warning is the one to weigh.

Will lemon juice or citric acid work instead?

Fellow publishes a citric acid method for its kettles and actually prefers it to vinegar, on the grounds that it is a bit stronger and does not leave a lingering smell behind. That is one manufacturer speaking about its own kettles. None of the other four we read publishes a lemon juice or citric acid quantity for a kettle, so if yours is not a Fellow, this is a question for your own documentation rather than something to work out from a fruit. Whatever acid you use, the rinsing at the end matters more than the choice.

How do I know I have rinsed it enough?

Use your nose. Smeg tells you to fill, boil and empty at least twice after descaling, and De'Longhi gives essentially the same thing — boil, empty and repeat once more. Treat two full cycles as the floor rather than the target, and keep going until there is no smell of vinegar or descaler in the water. Then make one drink and pour it away. If that drink tastes wrong, rinse again.

Sources

Every specification on this page is traced to one of these sources. Tier 1 is a manufacturer document, a published standard, or a government safety authority. See Standards for the full tiering rule.

  1. Tier 1Breville Crystal Clear Kettle BKE595 Instruction ManualBreville · accessed 2026-07-29 · re-verification due 2027-01-25
  2. Tier 1Smeg Kettle Maintenance InstructionsSmeg UK Ltd · accessed 2026-07-29 · re-verification due 2027-01-25
  3. Tier 1How do I descale my kettle? (FAQ)De'Longhi · accessed 2026-07-29 · re-verification due 2027-01-25
  4. Tier 1Is Descaling Necessary? How Often to Descale a KettleFellow Products · accessed 2026-07-29 · re-verification due 2027-01-25
  5. Tier 1How to reduce limescale in your Dualit appliancesDualit Ltd · accessed 2026-07-29 · re-verification due 2027-01-25

Revision history

Current version 1 · updated 2026-07-29 · next review due 2027-07-29

  1. v1 · 2026-07-29First draft. Sourced to Breville, Smeg, De'Longhi, Fellow and Dualit documentation read on 2026-07-29. No value publishes as verified. The agent, the quantity, the heating instruction, the interval and the fill capacity all publish as consult-the-manufacturer, and three of them carry a documented disagreement between named manufacturers rather than a house figure. Two Russell Hobbs support articles and one Fellow help-centre article returned HTTP 403 and were not registered.

Corrections to this page are listed in the public corrections log. Reports that are credible and not yet verified are listed in the public errata register, and an open one renders above the step it concerns.

Comments and corrections

Found an error? A correction with a manufacturer source is applied and logged publicly. You can also write to corrections@fixchecklist.com.

Every step above carries its own report control, which tags the report with that step so a correction reaches the right place. For anything about the procedure as a whole — the order of the sections, a step that is missing, something that did not match your equipment — use this: report something about this whole procedure.

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