How to backflush an espresso machine (water only)
A water backflush is the quickest habit that keeps an espresso machine's group head clean: it flushes coffee oils out of the three-way valve and the passages behind the shower screen before they turn rancid. It takes under a minute and needs nothing but a blind filter.
What you need
- Blind filter
How to do it
- Insert a blind filter into your portafilter
- Lock the portafilter into the group
- Activate brew for 10s, then stop for 10s
- Repeat 3–5 cycles
- Rinse the portafilter under the tap
Tips from the bench
Collected from manufacturer guidance and years of home-barista forum wisdom:
- Short pulses beat one long run: five to ten seconds on, then release. The release is the moment the three-way valve spits debris into the drip tray.
- Watch the drip tray water. When it runs clear instead of brown, you are done.
- Do it at the end of a session while the group is hot. Warm water dissolves coffee oils far better than a cold flush.
For machines with a 3-way solenoid. Without one: you'll need a backflush kit or you can skip this.
How often?
Recommended cadence by machine type, from the maintenance data behind the Espremo app:
| Machine type | Frequency |
|---|---|
| E61 HX | Weekly |
| E61 Dual Boiler | Weekly |
| Non-E61 Dual Boiler | Weekly |
| Single Boiler | Weekly |
Machines that run their own cleaning cycle (like the Breville Oracle series) handle some of this automatically — cadence also shifts with water hardness and daily shot volume.
Never miss this task again
Espremo is a free iPhone app that builds a maintenance schedule for your exact machine — covering 108 models — and taps you on the shoulder when something is due.
Download on the App Store