Quick answer: Backflushing uses a solid "blind" basket to force water, and sometimes espresso detergent, back up through the group head and out the machine's three-way valve, clearing coffee oils and grounds. Commercial cafés typically backflush with detergent daily at close and with plain water between rushes. Only machines with a three-way valve should be backflushed; always follow your manufacturer's instructions.
Key takeaways
- Backflushing cleans the inside of the group head that wiping can't reach.
- Daily with detergent at close; water-only between rushes.
- You need a blind basket and a three-way valve machine.
- Always rinse thoroughly and pull a discard shot afterward.
What backflushing does
Every shot leaves coffee oils and fine grounds in the group head, shower screen and valve. Over a day they build up and turn rancid, adding bitterness and off-flavors to every shot. Backflushing blocks the portafilter's outlet with a solid basket, so when you run the pump, pressurized water has nowhere to go but back up through the group and out through the three-way valve, carrying residue with it.
Can your machine be backflushed?
Backflushing requires a three-way solenoid valve, which releases pressure from the group after each shot. Most commercial machines have one. Some machines, especially certain lever groups and machines without that valve, should not be backflushed. Check your manual first.
What you need
- A blind basket (solid, no holes) for each group, or one you move between groups
- An espresso machine detergent in powder or tablet form
- A group head brush
- A towel and a rinse cup
Step by step (detergent backflush)
Using a popular powder detergent as an example, the label directions for traditional machines are roughly:
- Insert the blind basket and add the detergent dose. For that product it's about ½ teaspoon (3 g) per group.
- Lock in the portafilter and run the brew cycle for about 10 seconds, then stop for 10 seconds. Repeat five times.
- Remove the portafilter and rinse it under the running group.
- Lock it back in and repeat the 10-on/10-off cycle five more times without detergent to rinse.
- Pull and discard a shot to make sure no residue or taste remains.
Repeat for every group.
How often
| Situation | What to do |
|---|---|
| Between rushes | Water-only backflush or a quick flush and brush |
| End of every service day | Detergent backflush, every group |
| Weekly | Remove and clean shower screens; soak baskets and portafilter spouts |
For commercial machines in regular use, a detergent backflush is usually part of the daily end-of-service routine. Some manufacturers recommend limiting detergent backflushes to avoid stripping lubricant from group components, so follow your machine's guidance.
Common mistakes
- Skipping the rinse cycles. Detergent left in the group will taste terrible in the first shot.
- Using the wrong product. Use detergents made for espresso machines.
- Forgetting the gasket. Brush around the gasket and screen; backflushing doesn't reach everything.
- Soaking parts that shouldn't be soaked. One detergent's soak ratio is 1 teaspoon per 32 oz of water for baskets and spouts, but keep handles and plastic parts out unless allowed.
For the complete daily, weekly and monthly routine, see our espresso machine cleaning checklist.
Keep the bar stocked
Add detergent, blind baskets and spare gaskets to your par sheet alongside cups and lids. Affogato Bean keeps your branded cups, lids, sleeves and napkins on a recurring schedule with Affogato Reserve. See products.
Always follow your equipment manufacturer's instructions and your detergent's label directions.
Frequently asked questions
How often should you backflush an espresso machine?
For commercial machines in regular use, backflush with espresso machine detergent once a day at the end of service, and with plain water between rushes. Follow your manufacturer's instructions, which take priority.
Can every espresso machine be backflushed?
No. Backflushing requires a three-way solenoid valve that relieves pressure from the group. Machines without one, and some group designs, shouldn't be backflushed. Check your manual.
What do you use to backflush an espresso machine?
A blind (solid) basket in the portafilter and a detergent made for espresso machines. One common powder detergent calls for about half a teaspoon, or 3 grams, per group.
Sources
- Crema (retailer listing), “Urnex Cafiza Cleaning Powder — instructions for traditional espresso machines.”
- Ozone Coffee, “Urnex Cafiza2 Espresso Machine Cleaning Powder — FAQ.”
- WebstaurantStore, “Urnex Cafiza 20 oz. Espresso Machine Cleaning Powder.”
Sources checked October 2026. Statistics are reported as published by each source.