How to Descale an Espresso Machine (Complete Guide)

Run a descaling solution or citric acid mix through your machine’s water system every 2-3 months, depending on your water hardness. Skip this and you’ll be pulling shots through a machine whose boiler is slowly filling with limescale. That’s an expensive fix, not a cheap one.

I’ve descaled hundreds of machines behind the bar and dozens more at home since 2021. The process is the same whether you’re running a $150 De’Longhi or a $2,000 Breville. What changes is how often you need to do it and what solution you should use.

Why Descaling Actually Matters

Tap water carries dissolved calcium and magnesium. Every time your machine heats water, some of those minerals drop out of solution and stick to whatever they touch: heating elements, boiler walls, internal tubing. That’s limescale. It doesn’t rinse away with regular use.

Here’s the part people don’t think about: limescale insulates. Your heating element has to work harder to reach brew temperature. That means longer heat-up times, temperature instability shot to shot, and eventually a thermostat or heating element that fails early. I’ve torn down machines with three-year-old scale buildup that looked like a cave formation. The owner’s excuse was always the same: “it still made coffee.” Sure. Badly, and on borrowed time.

How Often You Actually Need to Descale

Forget the generic “every 3 months” sticker on the box. Your real interval depends on water hardness, measured in grains per gallon (GPG) or parts per million (ppm).

Don’t know your water hardness? A $12 test strip from any hardware store tells you in 30 seconds. I test every new home setup I review before I even pull a shot. It’s that foundational to how a machine performs. Seattle water runs soft, around 2-3 GPG. Phoenix and most of the Southwest sits well above 10 GPG. If you’re already using filtered or bottled water for your machine, you can stretch toward the soft-water end of that range regardless of your tap.

Breville’s own maintenance guidance for machines like the Barista Express tells you to descale when the indicator light triggers. That’s calibrated to shot count, not calendar time, and it’s smarter than a flat “every 90 days” rule. De’Longhi builds similar sensors into their higher-end Dinamica and Eletta lines. If your machine has that light, trust it over a sticky note on your fridge.

Citric Acid vs. Proprietary Descaling Solution

This is where I get the most questions, and the answer isn’t as simple as “they’re all the same.”

Citric acid is cheap, food-safe, and effective against calcium carbonate scale. Mix 1-2 tablespoons of food-grade citric acid powder into 32 oz of water and you’ve got a working descaling solution for a fraction of the cost of a branded packet. I use this on my own machines at home.

Proprietary solutions like Breville’s descaler, De’Longhi’s EcoDecalk, and Durgol’s Swiss Espresso use specific pH buffers and corrosion inhibitors tuned to the metals in that manufacturer’s boiler and internal lines. Durgol in particular tests clean on stainless steel without the etching risk that straight citric acid can cause with repeated use on some alloys.

My honest take: if your machine’s still under warranty, use the manufacturer’s solution or an approved equivalent. Once you’re out of warranty, citric acid does the job for less money. Just don’t use vinegar. It’s weaker against calcium scale, and the smell lingers in your machine’s lines for weeks. I tested this early on and regretted it.

The Descaling Process, Step by Step

1. Empty and refill the water tank with your descaling solution. Follow the ratio on the packet, or use 1-2 tablespoons citric acid per 32 oz water.
2. Remove the water filter if your machine has one. Descaling solution will degrade carbon filters.
3. Run the solution through the brew head in short bursts. Most machines want 20-30 seconds on, then a pause, repeated until the tank’s empty. Check your manual. Some auto-machines, like De’Longhi’s bean-to-cup line, have a built-in descale cycle you trigger through the menu.
4. Run it through the steam wand too. People skip this constantly, and it’s exactly where I find the worst buildup on teardown.
5. Refill the tank with plain water and run it through fully, twice. This flushes residual solution out of the lines. Skip this step and your next shot tastes like a chemistry set.
6. Reinsert your water filter and run one more tank of plain water before brewing anything you plan to drink.

The Real Bottleneck: It’s Not the Descaling, It’s the Water

Here’s what six years behind commercial machines taught me: descaling treats the symptom. Water filtration treats the cause. If you’re on hard water and skipping filtration entirely, you’re fighting a losing battle no matter how religiously you descale.

A basic in-tank water filter, the kind that ships with most Breville and De’Longhi machines, pulls out a good chunk of hardness before it ever reaches your boiler. Replace it every 2-3 months. I’ve seen owners run the same filter for a year “because it still fits,” which defeats the entire point. If you’re serious about extending descale intervals and protecting a machine you paid real money for, pair filtered or remineralized water (SCA’s water standard targets 150 ppm total dissolved solids for brewing quality) with a filter cartridge on a real replacement schedule. That’s the actual fix. Descaling is just cleanup after the fact.

My Product Recommendations

• Breville Descaling Solution (4-pack): This is what I keep on hand for every Breville machine I test, including my own Barista Express. It’s built for their boiler alloy specifically, and using it keeps warranty claims clean if something else goes wrong down the line.
• De’Longhi EcoDecalk Descaler: I’ve run this through three different De’Longhi bean-to-cup machines during reviews. No residue smell after the rinse cycle. That matters more than people expect until they’ve dealt with the alternative.
• Durgol Swiss Espresso Decalcifier: My go-to recommendation for anyone with a higher-end machine outside warranty. Fast-acting, gentler on internal seals than straight citric acid in my long-term testing, and it works across brands.
• Baratza Grinder Cleaning Tablets: Not for your machine’s water system, but if you’re deep-cleaning your setup, don’t ignore the grinder. Stale oil buildup on burrs affects flavor more than most people realize. Baratza’s tablets are the easiest fix I’ve tested.
• Third Wave Water Mineral Packets: If you’re serious about cutting how often you need to descale at all, remineralizing your water at the source reduces scale buildup dramatically. I switched to this at home and stretched my descale interval by nearly two months.

— Nora Voss, Home Barista & Coffee Equipment Reviewer