Backflushing Your Machine

Backflushing forces water — and optionally detergent — back through the group head and the three-way solenoid valve, then out through the valve's drain. This clears coffee oils and fine residue from places you can never reach by wiping. It is a core part of routine maintenance.

Backflushing is not descaling

These two jobs are constantly confused:

• Backflushing removes coffee oils from the group head and solenoid valve.
• Descaling removes mineral scale from the boiler.

You need both, on different schedules, and neither replaces the other. Backflushing does nothing for scale; see descaling.

Which machines can be backflushed

Detergent backflushing only works on machines with a three-way solenoid valve, which releases group pressure back through a drain:

• Solo
• Flux
• Duo

Do not detergent-backflush the Pico (no solenoid) or the Lever (manual group). On those, detergent has nowhere to drain and can be forced back into the pump or boiler. A plain water rinse of the group and basket is the correct routine for them. Check compatibility if you are unsure what your machine has.

Detergent backflush (weekly)

You need a blind (unperforated) basket. Work through the steps:

1. Remove the normal basket from the portafilter and insert the blind basket.
2. Add one BrewCraft Cleaning Tablet, or about ½ teaspoon of backflush detergent, onto the blind basket.
3. Lock the portafilter into the group and start the brew cycle as if pulling a shot. Water pumps against the blind basket and pressure builds — nothing comes out the bottom.
4. After about 10 seconds, stop the pump. The three-way valve releases the built-up pressure, pushing cleaner back through the group and out the drain. You will see dirty, soapy water appear in the drip tray.
5. Repeat the on/off cycle 5-8 times, roughly 10 seconds on and a moment off each time, until the water in the tray runs clear with clean foam.
6. Remove the portafilter, take out the blind basket, and rinse it thoroughly to remove all detergent. Reinsert the empty blind basket and run 5 more on/off cycles with clean water and no detergent to flush every trace of cleaner out — residue tastes bad and is not safe to leave.
7. Wipe the group head and shower screen with a clean cloth, then reinstall the normal basket and pull a throwaway shot.

Water-only backflush

A plain-water rinse — same blind basket, no detergent — can be done far more often, even daily, to keep the screen and valve clear between detergent cleans. Just run several 10-second on/off cycles with clean water.

Note: BrewCraft Cleaning Tablets are currently out of stock. In the meantime, keep up with water-only backflushing, or use a compatible backflush detergent at the dose above.

Pair this with the wider care routine in maintenance and descaling.