Descaling with a tablet takes 20 to 30 minutes and removes mineral buildup that slows water flow

Descaling tablets dissolve mineral deposits inside your Breville espresso machine's internal pipes and boiler. Over time, minerals from water accumulate and restrict water pressure, making shots pull slowly and unevenly. A descaling tablet breaks down these deposits so water flows freely again. Most Breville machines signal when descaling is needed—usually after 200 to 300 shots, depending on your water hardness.

The process is straightforward: you fill the water tank with a tablet dissolved in water, run the solution through the group head and steam wand, let it soak, then flush the machine with fresh water. You do not need to disassemble anything. Breville sells its own descaling tablets, but any espresso machine descaling tablet formulated for the same water volume will work.

Key Takeaways

  • Fill your water tank with hot water and one descaling tablet, then let it dissolve completely before starting.
  • Run the solution through the group head for 10 seconds, then through the steam wand for 5 seconds, alternating until the tank is empty.
  • Let the machine sit for 15 to 20 minutes with the solution inside, then repeat the flushing cycle.
  • Refill the tank with fresh water only and run it through both outlets until the water runs clear—this takes two full tanks.
  • Descale every 40 to 80 shots if your water is hard, or every 200 shots if your water is soft.

What you need before you start

Gather a descaling tablet (Breville brand or a universal espresso machine tablet), your water tank, a cup or pitcher to catch liquid, and access to fresh water. Check your machine's manual for the exact tablet dosage—most Breville models use one tablet per full tank, but some compact models use half a tablet. If you are unsure, one tablet dissolved in a full tank is the standard starting point.

Make sure your machine is turned on and has reached operating temperature. The heating element works better when warm, and the solution flows more easily through hot pipes. If your machine has a descaling mode or button, locate it now—some Breville models have a dedicated setting that automates part of the cycle. Check your manual or the Breville website for your specific model number to confirm whether yours has this feature.

Dissolving the tablet and filling the tank

Fill your water tank with hot water from the tap—not boiling, just hot enough to dissolve the tablet quickly. Drop the descaling tablet into the tank and let it sit for 2 to 3 minutes, stirring occasionally with a spoon or small stick. The tablet should dissolve completely; if pieces remain, stir longer or use slightly hotter water. A fully dissolved solution is clear or slightly cloudy, never grainy.

Once dissolved, insert the tank back into your machine. Position a cup or small pitcher under the group head to catch the descaling solution—you will be running liquid through for several minutes. Place another cup under the steam wand. The solution is not toxic, but it tastes bitter and can stain, so avoid splashing it on your clothes or countertop.

Running the solution through the machine

Turn on the group head and let the solution flow for 10 seconds, then turn it off. when ready switch to the steam wand and let it run for 5 seconds. Alternate back and forth—10 seconds group head, 5 seconds steam wand—until the water tank is empty. This cycle takes about 8 to 12 minutes depending on your machine's flow rate. The solution will be dark brown or black as it carries out mineral deposits.

Do not let the machine run continuously; alternating between outlets ensures the solution reaches all internal passages. If your machine has a three-way solenoid valve (a small lever or button on the side), you may need to open it between cycles to release pressure and let solution drain from the group head. Check your manual for this step—not all Breville models have it, but if yours does, opening it prevents backflow and speeds up the process.

Letting the solution soak inside the machine

Once the tank is empty, turn off the machine and let it sit for 15 to 20 minutes. During this time, the descaling solution works on stubborn mineral deposits inside the boiler and pipes. You do not need to do anything—just wait. If your machine has a descaling mode, it may automate this pause and alert you when the soak is complete.

While you wait, rinse out your water tank thoroughly under running water. Remove any tablet residue or mineral particles clinging to the inside. This step prevents undissolved particles from entering the machine during the rinse cycle that comes next.

Flushing the machine with fresh water

Refill the tank with fresh, cold tap water. Run it through the group head and steam wand using the same alternating pattern: 10 seconds group head, 5 seconds steam wand. Continue until the tank is empty. The water will still look slightly discolored—this is normal and means minerals are still being flushed out.

Refill the tank a second time and repeat the flushing cycle. After the second tank, the water running from the group head should be clear or nearly clear. If it still looks brown or cloudy, run a third tank through. This thorough rinsing removes all traces of descaling solution, which can affect the taste of your espresso if left inside.

Testing your machine and preventing future buildup

Once flushing is complete, pull a test shot into a cup. The espresso should flow at a normal rate—not too fast, not too slow. If the shot pulls slowly, mineral buildup may still be present; run another round of fresh water through the group head and try again. A properly descaled machine pulls a double shot in 25 to 30 seconds.

To extend the time between descaling, use filtered water in your machine instead of tap water. Filtered water contains fewer minerals and slows buildup significantly. If you live in a hard-water area, descale every 40 to 80 shots. If your water is soft or filtered, descale every 200 shots or when your machine signals that it is time.

Common mistakes to avoid

Do not use a tablet that has not fully dissolved—undissolved particles can clog the group head or steam wand. If you see graininess in the tank, let it soak longer or use hotter water before inserting it into the machine. Do not skip the soak step; running solution through and when ready flushing wastes the tablet's cleaning power. The 15 to 20 minute soak is when most of the mineral breakdown happens.

Do not forget to flush thoroughly. Leftover descaling solution will make your next espresso taste sour or metallic. If your espresso tastes off after descaling, run another full tank of fresh water through the machine. Also avoid descaling more often than necessary—the solution is mildly acidic and repeated use can wear internal seals over time. Descale only when your machine signals the need or when you notice slow flow.

Frequently Asked Questions

Can I use a generic descaling tablet instead of Breville brand?

Yes. Any espresso machine descaling tablet formulated for your tank size will work. Generic tablets are usually cheaper and perform the same job. Make sure the tablet is designed for espresso machines, not for coffee makers or kettles, because the concentration differs. Check the package to confirm it is safe for your machine's materials.

What if my machine still has slow flow after descaling?

Run a second descaling cycle. Some machines with heavy mineral buildup need two treatments. If flow is still slow after a second descale, the problem may be a clogged shower screen or group head gasket rather than internal deposits. Remove and rinse the shower screen under hot water, or contact Breville support if the issue persists.

How do I know if my water is hard or soft?

Hard water leaves white or chalky deposits on faucets and shower heads. If you see buildup around your kitchen tap, your water is hard and you should descale every 40 to 80 shots. If you do not see deposits, your water is likely soft and descaling every 200 shots is sufficient. You can also purchase an inexpensive water hardness test kit at a hardware store.

Is descaling solution safe if it splashes on my skin?

Descaling solution is mildly acidic but not caustic. If it splashes on your skin, rinse the area with water. It will not cause burns or serious irritation. Avoid getting it in your eyes; if that happens, rinse thoroughly with water and seek medical attention if irritation continues.

Can I descale my Breville while it is still hot?

Yes. In fact, a warm machine descales more effectively because the solution flows more easily through hot pipes. Let the machine reach operating temperature before you start. Do not touch the group head or steam wand during the process, as they will be hot.