Back flushing is one of the most important cleaning routines for maintaining a semi-professional, single boiler, or commercial espresso machine. Done regularly, it helps remove built-up coffee oils and fine grounds, reducing the risk of blockages and keeping your machine performing properly.

This guide walks through both types of back flushing: with and without cleaning detergent.

What Is Back Flushing?

Back flushing is a cleaning process that forces water (and sometimes detergent) backward through the group head and internal pathways of an espresso machine.

This process helps:

Remove leftover coffee oils
Clear fine coffee debris
Reduce buildup in the group head, solenoid valve, and screen
Prevent blockages and long-term mechanical issues

There are two types of back flushing:

Water-only back flushing (routine maintenance)
Detergent back flushing using a cleaning agent such as Cafiza (deep cleaning)

Both are important and serve different purposes.

How Often Should You Back Flush?

Water-Only Back Flushing

Home use: Every 1–2 days
Commercial use: Daily

This prevents coffee oils from drying and hardening inside the machine.

Back Flushing With Cafiza (Detergent)

Home use: Once per week
Commercial use: Every 1–2 days, depending on volume

Detergent back flushing targets deeper oil buildup that water alone cannot remove.

What You’ll Need

A blind filter basket
Espresso machine cleaning detergent (such as Cafiza)
A group head brush
Your portafilter

How to Back Flush Your Espresso Machine

Step 1: Prepare the Portafilter

Remove the regular basket from the portafilter and insert the blind basket.

For detergent cleaning, add ¼ teaspoon of Cafiza to the blind basket.

Step 2: Run the Back Flush Cycle

Insert the portafilter into the group head.

Run the pump for 10 seconds
Stop and let it sit for 10 seconds
Repeat this cycle 5–6 times

This allows pressure to build and release, effectively cleaning internal components.

Step 3: Rinse After Detergent Cleaning

If you used Cafiza:

Repeat the same back flushing process without detergent
This ensures all cleaning residue is fully flushed out

Never skip this step.

Step 4: Clean the Group Head

Once back flushing is complete:

Use an angled group head brush
Clean around the group gasket and shower screen
Remove any loosened residue

Step 5: Finish Up

Reinsert the portafilter into the group head when finished.

This helps:

Maintain heat
Keep the gasket from drying out
Ensure consistent performance

Why Back Flushing Matters

Skipping or delaying back flushing increases the risk of:

Blocked solenoid valves
Poor water flow
Bitter or stale flavors
Costly repairs

Regular back flushing keeps your machine clean, reliable, and producing better-tasting espresso.

About This Guide

Written by Julian Lall
Barista & Sales Representative

This guide is part of our Cleaning & Maintenance resources and reflects real-world espresso bar and service experience.

How to Back Flush a Semi-Professional Espresso Machine