Solid light or flashing light?
- Solid on: it’s time to descale. source
- Flashing: it’s time for the cleaning cycle, which uses a cleaning tablet and the cleaning disc. That’s a different job. source
Breville doesn’t give a set number of weeks. Wait for the light.
Step by step
These steps come straight from Breville’s instruction book for the Barista Express (BES870XL).
- Check the CLEAN / DESCALE light. Solid on means descale now. source
- Dissolve one Breville descaling powder sachet in 1 liter (34 fl oz) of water and fill the water tank. source
- Warning from the manual: keep water in the tank the whole time. Do not remove the tank or let it run empty. source
- Hold the 2 CUP button, then also hold POWER, to enter descale mode. The machine heats up (POWER flashes). source
- Ready when POWER, 1 CUP, CLEAN/DESCALE and HOT WATER/STEAM lights are all solid. source
- Put a large container under the portafilter spouts. Press 1 CUP to descale the coffee side (about 25 seconds). source
- Turn the steam dial RIGHT to descale the steam wand (about 13 seconds); turn it LEFT for the hot water outlet (about 8 seconds). source
- You can stop a steam or hot water pass early by turning the steam dial to STANDBY. source
- About half the solution (0.5 L / 17 fl oz) should be left in the tank after the first pass. source
- Repeat the coffee, steam, and hot water steps until the tank is empty. source
- Rinse: remove the tank, rinse it well, fill with fresh cold water to MAX (2 L / 68 fl oz), and repeat the coffee, steam, and hot water steps. source
- Press POWER to exit. The machine also shuts itself off after 5 minutes with no action; restart from the descale-mode step. source
Using a different descaler than Breville’s? Follow its label for how much to mix into the liter of water. The rest of the steps stay the same.
Can I use vinegar?
Breville’s manual only mentions its own descaler, and doesn’t mention vinegar at all. Breville’s cleaning blog does give a vinegar mix of 1 part water to 1 part vinegar source. Since the manual only names a descaler, a descaler made for espresso machines is the safe choice.
Descale less often
Change the water filter in the tank every two months, says Breville. It cuts down on scale. source
Breville’s own BWF100 charcoal filters, the kind the Barista Express uses. Six in a pack, about a year’s worth.
Cleaning tablets for the cleaning cycle (the flashing light).
If it’s weak after descaling
Scale that breaks loose can get stuck inside. Owners describe these signs:
- “The most common problem with thermocoil machines (and their cheaper cousins the thermoblock machine) is scaling of the passageways.” (owner report)
- “Scale from descaling the thermocoil often gets caught in the solenoid block or the right angle connector on the input to the block.” (owner report)
- “When I brew a shot, only the top of the puck gets wet and all water is in the drip tray.” (owner report)
If that happens, run another rinse cycle with fresh water. If water still won’t flow, contact Breville support.