How to Descale a Breville Barista Pro (BES878), Step by Step

How the Barista Pro Descales Itself

On a Breville Barista Pro (BES878), descaling runs from the menu, not a button combination. When the LCD shows DESCALE, take the water filter out, fill the tank to the DESCALE line with descaler, then press MENU, select DESCALE with the GRIND AMOUNT dial, and press 1 CUP. The machine runs three stages, coffee, hot water and steam, then a three-stage rinse.

The one part you do by hand is the steam dial. The book says it "must be manually turned to the HOT WATER and STEAM position when indicated on the LCD", during both the descale and the rinse. Miss a prompt and the cycle waits.

Breville's reason to do it: hard water leaves mineral build-up that reduces "the brewing flow, brewing temperature, power of the machine, and the taste of the espresso". The book gives no calendar interval. The LCD tells you when.

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What You'll Need

None of Breville's espresso books mentions vinegar. The BES878 book just says to add "the descaling agent". Use Breville's descaler and its dose.

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Step 1: Empty the Tray and Remove the Filter

1. Empty the drip tray and put it back on the machine.
2. Lift off the water tank.
3. Remove the water filter from the tank. The book makes this the first step.

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Step 2: Fill to the DESCALE Line

1. Fill the tank with water to the DESCALE line marked on it.
2. Add the descaling agent and mix.
3. Refit the tank and press it down until it's locked in.

Keep the tank in place from here on. The Barista Express and Bambino books warn never to remove or completely empty the tank during descaling, and the same caution makes sense here.

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Step 3: Start DESCALE From the Menu

1. Press MENU.
2. Turn the GRIND AMOUNT dial to DESCALE and press the dial to select it. The 1 CUP button lights up.
3. Put containers under the group head, the steam wand and the hot water outlet.
4. Press 1 CUP to start.

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Step 4: Follow the Three Descale Stages

The cycle runs coffee, then hot water, then steam, and the machine beeps after each stage.

1. Let the coffee stage run through the group head.
2. When the LCD indicates it, turn the steam dial to HOT WATER.
3. When the LCD indicates it, turn the steam dial to STEAM.

⚠️ Safety: solution from the wand and hot water outlet comes out hot. Keep hands clear. Breville warns that "pressurized steam can still be released, even after machine has been switched off".

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Step 5: Run the Rinse Cycle

When descaling ends, the 1 CUP button lights again. The machine needs a rinse.

1. Empty the drip tray and put it back.
2. Pour out any descaling liquid left in the tank, rinse it, and fill it with fresh water to MAX.
3. Refit the tank.
4. Press 1 CUP. The rinse also runs in three stages, and the LCD shows which one it's on.
5. Turn the steam dial when the LCD asks, as before.
6. When it's done, the machine beeps and returns to READY.

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Step 6: Clean Up and Refit the Filter

1. Remove and rinse the drip tray and the water tank, and dry them thoroughly.
2. Put a filter back in the tank. Breville says to replace the filter every 2 months, sooner in hard water.
3. Refill with fresh, cold water.

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Troubleshooting the Procedure

Comparing models? Our Breville descale light guide sets out each Breville's sequence side by side.

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The FLUSH Cleaning Cycle

The LCD shows FLUSH when the group head needs a back-flush. It's a separate maintenance job, and doing one doesn't replace the other.

1. Put the cleaning disc in the filter basket and a cleaning tablet on top.
2. Lock the portafilter in.
3. Empty the drip tray, and fill the tank to MAX.
4. Press MENU, turn the GRIND AMOUNT dial to FLUSH, and press it. 1 CUP lights up.
5. Press 1 CUP. The LCD shows the time remaining.
6. When it beeps back to READY, check the tablet has dissolved, and repeat if it hasn't. Rinse the portafilter, disc and drip tray.

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Scale Less Often

• Change the water filter every 2 months, sooner in hard water. Breville says this "will reduce the need to de-scale the machine".
• Don't use highly filtered, demineralized or distilled water. The BES878 book says not to.
• Fill with fresh, cold tap water daily, as the book recommends.
• Purge the group head before a shot: press 1 CUP briefly with no portafilter to stabilize the temperature.

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FAQ

How often should I descale a Barista Pro?

When the LCD shows DESCALE. The BES878 book doesn't give a time interval. It has the machine flag the job, and changing the water filter every two months reduces how often that happens.

Does the Barista Pro have a water hardness setting?

Not in its instruction book. The BES878 menu items in the book are shot programming, SHOT TEMP, FLUSH, DESCALE and RESET DEFAULTS. Touch-screen Brevilles such as the Barista Touch and Oracle Touch do have a Water Hardness setting.

Does RESET DEFAULTS clear the descale alert?

The book says RESET DEFAULTS restores the grind amount, filter size, shot temperature and the 1 CUP and 2 CUP settings. The descale alert isn't on that list. Run the descale and rinse instead.

Can I use vinegar in a Barista Pro?

The BES878 book doesn't mention vinegar either way; it only says to add "the descaling agent". We'd use Breville's descaler at the packet's dose rather than guess at a vinegar ratio for a machine whose maker never gives one.

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Related Breville Guides

• Barista Pro Not Working?: every LCD message and the thermal cut-out
• Barista Pro Not Heating?: pre-heating and SHOT TEMP
• Breville Descale Light Won't Turn Off?: sequences for every Breville
• How to Descale a Barista Express: the BES870's button-driven version
• Barista Express & Pro Maintenance Schedule: cleaning, descaling, filter and burrs by prompt

Sources: Breville Barista Pro BES878 Instruction Book.