The DeLonghi Dedica is, quite rightly, the perfect entry-level espresso machine for many. With the right upgrades and a small grinder by its side, the Dedica can make many larger espresso machines look old.
However, the Dedica only works well as long as the water flows through the internal tubes without becoming calcified. The thermoblock in particular builds up limescale over time, even with water that has low hardness (magnesium and calcium). That is why regular descaling is essential.
This should take place at the very least when the orange warning light comes on. If your tap water is on the "harder" side, more frequent descaling is actually advisable.
In this article, we explain step by step how to do this and when you should descale. Our video can also help you with this.
Go directly to the step-by-step guide
Don't want to descale alone? Join us for our stream on YouTube.
Next descaling party: Wednesday, August 27, 2025 at 6:00 PM. Click here for the live stream.
Limescale, the enemy of every machine
What is this limescale anyway, and why is it such a nuisance? It's simple: our tap water contains dissolved minerals, primarily calcium and magnesium. When heated in your espresso machine, these minerals precipitate and deposit as a hard, white layer. This is limescale. These deposits act like an insulating layer on the heating elements, which means your machine has to use more energy to reach temperature. Furthermore, the fine pipes and nozzles can clog, which affects water pressure and temperature. The result? Your coffee often tastes sourer and no longer delicious! This is often because calcified machines no longer brew at a high enough temperature. And that then leads to sour coffee.
Orange alert: Dedica needs descaling
If the right steam button lights up orange, it is time to descale your machine. At the very latest, this is the right time. Your machine needs your attention!
Sometimes, you may read in general DeLonghi instructions or for newer models like the Dedica Arte about a "red descaling light." This can be a bit confusing at first. If you have a Dedica EC685 or a similar model, it is very likely the orange light on the steam button that is guiding you. However, this small ambiguity regarding the colors should not unnerve you. The important thing is that you pay attention to your machine's signal. In case of doubt, a look at your specific model's user manual always helps.
Rules of thumb – If the lamp is silent:
But what if the lamp is still fast asleep, but you feel like it's been ages since you last descaled? Here are a few rules of thumb:
- Regardless of the indicator light, it is good practice to treat your machine to a descaling every two to three months. This prevents stubborn deposits.
- This guideline is especially applicable if water with more than 15 degrees of German hardness comes out of your tap. You can find this out via your local water supplier's website.
- If you are a true coffee lover and enjoy about 3-4 cups a day, then an interval of about 2 months is a very good rule of thumb.
The water hardness factor – Your local limescale check
A crucial point that is often underestimated is the water hardness at your home. The "harder" the water, the more lime is dissolved in it, and the faster deposits build up in your machine. This means that if you live in a region with very hard water, you may have to descale significantly more often, even if the warning light is not yet active. While the machine often has a water hardness setting that influences the timing for the descaling indicator, if your water is harder than the default setting, the limescale arrives faster than the machine "thinks.".
Kaffeemacher tip: How do you find out your water hardness? The easiest way is roughly via the water supplier's website or with test strips, or precisely with our water hardness test kit. With these so-called titration tests, you can determine the total hardness.
We have also written in detail on our blog about the topic of coffee water – it's worth taking a look! The result of your measurement will help you to optimally adjust the descaling intervals to your local conditions and not just act when a thick layer of limescale has already formed. This way, you avoid the "hidden costs" of not knowing – namely, potential machine damage and, most importantly: less delicious coffee.
Roughly speaking: over 15 German degrees of total hardness, it is better to descale more often than every three months. At 10 - 15 dH total hardness, descaling every 3 months is likely sufficient. Under 10 dH total hardness, the descaling periods can even be longer.
Always at your own risk, but this is a rough pointer.
The right descaler: our tip
Of course, the proprietary descaler from DeLonghi called EcoDecalk works. However, we have added another compatible descaler to our range and had it specially tested in the laboratory. This descaler can also be used for other thermoblocks, e.g., from Ascaso. It was actually developed for the professional descaling of Ascaso espresso machines, but as already written, it is also very well suited for the Delonghi Dedica.
Descaler that we use for our Dedicas and in the video.
Even if grandma swears by it: stay away from home remedies like pure citric acid to descale your espresso machine! When heated, citric acid can react with the limescale to form a compound called calcium citrate. The problem is that calcium citrate is insoluble and can actually clog the fine tubes of your machine—a true nightmare! Vinegar or vinegar essence are also not a good idea. The aggressive acid in vinegar can attack the metals and sensitive seals in your Dedica and make them porous.
What else you need:
- Collection container: You need one or, better, two vessels that can hold at least 1.5 liters of liquid together. Better to be a bit generous so nothing spills over during the process. A large mixing bowl, a measuring cup, or a small pitcher will serve you well here.
- Water: Clear, fresh tap water for mixing the descaling solution and—very important—for thorough rinsing later.
- Time window: Plan on about 25-30 minutes for the entire process. During this time, your Dedica can go through its "cure" in peace, and you can already look forward to the next, particularly delicious espresso.
Water filter? Please remove.
If you use a water filter in the tank of your Dedica (which is a great thing to generally reduce limescale deposits!), be sure to take it out before descaling. The descaler is not intended for the filter and could damage it or reduce its effectiveness. It will be used again later, after rinsing.
Here is everything at a glance in your personal checklist:
With this preparation, nothing can go wrong!
Descaling the Dedica – Step by Step
Everything ready? Great! Then let's roll up our sleeves and give your Dedica the well-deserved cleaning treatment. Just follow these steps, and it is really easy. If you are unsure, watch our video again or take part in the next descaling live stream.
1. Get the machine ready:
- First, turn your Dedica off if it happens to be on.
- Take the water filter out of the tank if you didn't already do so during preparations.
- Empty the water tank completely and rinse it briefly with fresh water to remove any residue.
- Now mix the descaler with water. Follow the instructions on the packaging of your descaler exactly. For the DeLonghi EcoDecalk, this is usually 100ml of descaler liquid per 1 liter of water. Of our descaler, you use one-third of the bottle, i.e., around 166 ml per liter. This corresponds to one tank filling of the Dedica.
- Fill the finished descaling solution into the water tank of your Dedica, but not beyond the MAX mark.
- Reinsert the filled water tank into the machine correctly.
2. Take position:
- Very important: The portafilter stays off! It is not inserted during the entire descaling process. This is crucial so that the solution can flow freely and does not get stuck in the portafilter.
- Now place a sufficiently large vessel (or one of your vessels, if you are using two) under the steam/milk frother (also known as the hot water spout). Position a second vessel under the brew head—exactly where the portafilter is normally inserted.
- Turn your Dedica on now using the ON/OFF button.
3. Wake up the descaling program:
- Wait a moment until the indicator lights for one and two cups are lit steadily. This indicates that your Dedica has heated up and is ready for use. Then the orange indicator light will also light up if the machine wants to signal that you should descale.
- When the indicator light is on, but even if it is not, you start the descaling process by firmly pressing the steam button for 10 seconds. You will know it worked when all three buttons (single cup, double cup, and the steam button) start flashing one after the other. That is the signal: descaling mode activated!
- Note: always check your manual briefly to see if it works the same way for your Dedica model.
4. Descaling in progress: operate the steam knob
- Turn the steam knob (the dial for the steam/hot water function) all the way to the steam position. This is usually marked by a steam symbol (similar to three wavy lines).
- Now press the right button (steam button—or the button you used to activate the mode) briefly once more to start the actual descaling process.
- The machine now begins to pump the descaling solution through the system in intervals. It also takes pauses while doing so—this is completely normal and part of the program.
Kaffeemacher pro tip – Absolutely observe!
So that not only the lines to the steam wand but also the brew head (the shower screen where the water meets your ground coffee) is thoroughly cleared of limescale, there is an important trick: Close the steam knob briefly every now and then (i.e., turn it to the "0" position). This forces the descaling solution to also flow through the brew head. After a few seconds (approx. 5-10 seconds), open the steam knob again. Feel free to repeat this every few minutes. Some instructions, such as those from DeLonghi itself for the Dedica Arte, suggest keeping the steam knob closed for a while after about 10 minutes to achieve this effect. This simple step makes a huge difference in the thoroughness of the descaling!
5. Tank empty? First round done!
The descaling process runs until the water tank with the descaling solution is completely empty. During the entire process, the orange indicator light on the steam button continues to flash, signaling that the machine is still in descaling mode.
You see, with a bit of patience and the right know-how, it is not that complicated.
After rinsing is before rinsing
The descaler has done its job and put an end to the nasty limescale deposits. But now the descaler itself has to come out of the machine! Thorough rinsing is super important now, because nobody wants the next espresso to have a slightly sour aftertaste of descaling agent.
1. Fresh water tank:
- The orange indicator light on the steam button is still happily flashing away—this is normal and shows that the descaling cycle (including rinsing) is not yet finished.
- Take the water tank out of the machine. If there is still a small amount of descaling solution in it, empty it completely.
- Rinse the water tank now very, very thoroughly with fresh, clear water. Preferably multiple times so that no descaler residue remains in the tank.
- Fill the clean water tank up to the MAX mark with fresh water. Ideally, as always when preparing coffee, soft water should be used here. We simply call this "coffee water" in our detailed article. If you use this water, you will have to descale less often.
- Reinsert the tank filled with fresh water correctly into your Dedica.
2. Start rinsing cycle:
- Empty the collection containers, which now contain the used descaling solution. Be a bit careful, as the solution can still be irritating. It is best to pour it directly into the drain. Then place the empty containers back under the steam outlet and the brew head.
- Make sure the steam knob is still in the steam position (symbol ).
- Now press the right button (steam button—or the button you also used to start the descaling) again to start the rinsing process.
3. Again the steam tap trick (Important during rinsing too!):
- Just like with the descaling itself, the same applies during rinsing: close the steam knob briefly every now and then. This ensures that the brew head and its lines are properly rinsed with fresh water and no descaling residues are left behind.
4. How often to rinse? The golden rule for clean lines:
- The machine now rinses the entire contents of the water tank through the system.
- We recommend—and DeLonghi itself also suggests this—to let at least one, but preferably two full water tanks of fresh water run through. This truly ensures that all descaler residues are removed. So, when the first water tank has been rinsed empty: simply repeat the process from point 1 ("Fresh water tank") for a second rinsing cycle. Better safe than sorry.
5. Water filter back in? Absolutely! (When exactly):
- If you use a water filter for your Dedica (which we highly recommend!), now is the right time to reinsert it. And ideally before you fill the tank with fresh water for the second rinsing cycle. So, place the filter into the empty tank, then fill it with fresh water and start the second rinsing cycle. This way, the filter is also rinsed through once with fresh water and is directly ready for the next coffee extraction.
Thorough rinsing is perhaps the most time-consuming part, but it is absolutely essential for the result. Take the time—it's worth it!
Finish line: The lamp going out
You've almost made it! Your DeLonghi Dedica will soon be as fresh and clean as the first day, ready for the next espresso and more. But how do you know that the descaling wellness cure is really completely finished?
The clearest sign is: The rinsing cycle (or the last rinsing cycle you performed) is finished when the water tank is empty again AND the orange indicator light on the steam button finally goes out.
Steam tap closed
A very important final step: Turn the steam knob back to the "0" position (closed). With this, you signal to the machine that the special "descaling/rinsing" mode is over and it can switch back to normal coffee mode.
Machine ready!
Fill the water tank with fresh water if necessary. Your DeLonghi Dedica is now officially descaled, freshly rinsed, and fully ready for the preparation of delicious espresso again!
Kaffeemacher's extra tips & tricks
Using soft (softened) water makes sense. The periods between necessary descaling sessions can be extended significantly. Especially if you live in a region with hard water, this is a real blessing for your machine and your schedule!
What if something hangs up? (Brief troubleshooting tips):
- Power failure during descaling? Don't panic! It is safest to restart the entire cycle (i.e., descaling AND rinsing) completely from the beginning to ensure that everything becomes clean and no descaling solution remains in the machine.
- Machine asking for another rinsing cycle? This can happen if the water tank was perhaps not filled completely to the MAX mark during a rinsing cycle. The machine is clever here and just wants to ensure that all descaler residue is really rinsed out. Simply follow the instructions on the display or the light signals.
Don't forget regular cleaning:
Descaling is an important part of machine maintenance, but not the only one! Do not forget the other regular cleaning of your Dedica either. This includes cleaning the portafilter and the baskets of coffee grounds and oils, wiping the shower screen, and cleaning the steam wand after every milk frothing. Click here for our article on cleaning the Delonghi Dedica.
Conclusion: Descaling ensures longevity
Regular and, above all, correct descaling is truly the key to a long-lasting DeLonghi Dedica that brings you pure joy, day after day, espresso after espresso.
Do you perhaps have more questions about descaling your Dedica? Or your own tips and tricks that you would like to share with the community? Then feel free to write them in the comments! We are always very happy to exchange ideas with you and also like to keep learning.
With that in mind: Here's to many more delicious and perfectly extracted espressos with your top-maintained DeLonghi Dedica!
Best, Ben Kaffeemacher
