How to descale an espresso machine

How we picked

We compared what espresso technicians, machine makers and consistent coffee reviewers recommend, then checked product specs and long-term owner feedback. The steps below follow the general process most manufacturers describe. Your machine’s manual always comes first.

Why scale builds up

Tap water carries dissolved calcium and magnesium. When water is heated, those minerals come out of solution and stick to boilers, heating elements, pipes and valves as limescale. Scale slows heating, narrows water paths and can block solenoid valves and steam wands. Left long enough, it is one of the most common reasons home espresso machines need repair.

How often to descale

It depends on how hard your water is and how much you use the machine. Many machines can be set to your water hardness and will remind you.

• Soft water, under about 60 ppm. Every four to six months.
• Medium water, about 60 to 120 ppm. Every two to three months.
• Hard water, over about 120 ppm. Every month or two.

Your local water report or a cheap hardness test strip tells you where you stand. Some machines include a strip in the box.

Descaler, citric acid or vinegar

Purpose-made descalers are the safest choice. Most use lactic, citric or sulfamic acid with additives that protect metal and help rinse. The De’Longhi EcoDecalk and Urnex Dezcal work in nearly any machine.

Plain citric acid works and is cheap. It can leave residue if you do not rinse well, and the right strength is up to you.

Vinegar is the one to avoid. Most espresso machine makers, including Breville and De’Longhi, advise against it. It is slow on heavy scale, can harm rubber seals and some metals, and leaves a smell that takes many rinses to clear. Using it can also complicate a warranty claim.

Step 1. Prepare the machine

Empty the drip tray and remove any water filter from the tank. Filters absorb descaler and stop it from reaching the boiler. Take out the portafilter and empty the bean hopper if your machine has a grinder that sits in the water path.

Step 2. Mix the descaling solution

Fill the tank with water and descaler at the ratio on the label. Dissolve powder fully in warm water in a jug before pouring it into the tank. Undissolved powder can settle in the boiler.

Step 3. Run the descale cycle

If your machine has a descale mode, start it and follow the prompts. If not, run the solution through the group head and steam wand in short bursts, pausing for several minutes between bursts so the acid has time to work. Stop when about half the tank has gone through, wait 15 to 20 minutes, then run the rest.

Step 4. Rinse thoroughly

Empty, rinse and refill the tank with clean water. Run at least one full tank through the group head, steam wand and hot water outlet. If you can still taste or smell descaler, run another tank.

Step 5. Reset and reinstall

Put the water filter back, reset the descale reminder if your machine has one and pull a test shot. Throw the first shot away.

Brand notes

Breville

Most Breville espresso machines, from the Bambino to the Barista Express and Barista Touch, have a dedicated descale program started from the buttons or menu. The steps differ by model, so follow the manual. Dual boiler models like the Oracle and Dual Boiler need their boilers drained through valves behind a panel. Breville’s own BES007 descaler is dosed for these programs.

De’Longhi

De’Longhi manual and bean-to-cup machines show a descale alert and run a guided cycle. De’Longhi recommends EcoDecalk and warns that other products can affect the warranty. Bean-to-cup models also need the water hardness setting matched to your water so the reminder comes at the right time. See our guide to bean-to-cup coffee machines for models that handle this well.

Nespresso

Original and Vertuo machines each have a descale mode entered by a button combination listed in the manual. Nespresso suggests descaling every few months or after a set number of capsules, more often with hard water. A liquid like the Impresa descaler is sized for these small tanks. See our guide to the best Nespresso machines.

Gaggia

The Gaggia Classic has no descale program. Run the solution through the group head and steam wand by hand in stages, as in step 3. Gaggia sells its own descaler, and owners often use a mild lactic or citric acid product on these machines.

Preventing scale

The best descale is the one you never need. Soft water slows scale a lot.

• A filter pitcher or the filter in your machine’s tank cuts some hardness and chlorine. It helps but does not fully soften hard water.
• Distilled water on its own is too pure. It can taste flat and some machines rely on minerals to sense water level.
• Distilled or reverse osmosis water remineralized with Third Wave Water Espresso Profile gives you consistent, low-scale water that still tastes good.

Pair a descaling routine with regular backflushing and cleaning. Our guide to espresso accessories covers the tools that make it easier.

Frequently asked questions

What happens if I never descale?

Scale slowly reduces heat and flow until valves block or the heating element fails. Shots get cooler and less consistent long before that.

Can I descale with vinegar?

You can, but most manufacturers advise against it. It can damage seals, leaves a lasting smell and works slower than a proper descaler.

Is descaling the same as cleaning?

No. Descaling removes mineral buildup inside the water path. Cleaning removes coffee oils from the group head, portafilter and baskets with a backflush detergent. Your machine needs both.

Do I need to descale if I use filtered water?

Yes, but less often. Most filters only reduce hardness. Check the descale reminder or watch for slower flow and cooler shots.