If your espresso tastes bitter, sour or inconsistent, the problem is often a dirty group head. Regular espresso machinegroup head cleaning removes built-up coffee oils and residue, improves extraction and keeps your machine running properly.
What Is the Group Head on an Espresso Machine?
The group head is the brewing component where the portafilter locks in and pressurised hot water flows through the coffee grounds. Because this area operates under high heat and pressure every day, it quickly accumulates coffee oils, fine particles, carbon deposits and burnt residue.
Without regular espresso machine cleaning and backflushing, this buildup can cause:
Bitter or sour tasting espresso
Slow or uneven extraction
Reduced water flow
Leaks around the group head gasket
Inconsistent crema
Routine group head cleaning is essential for maintaining proper pressure, water distribution and balanced coffee flavour.
What You Need to Clean an Espresso Machine Group Head
To properly backflush an espresso machine, you’ll need:
Both are formulated to dissolve coffee oils quickly without leaving residue or affecting taste when rinsed properly.
How to Clean an Espresso Machine Group Head (Backflushing Method)
⚠️ Only backflush machines fitted with a 3-way solenoid valve. Always check your manufacturer’s instructions first.
Step 1: Insert the Blind Filter
Remove your normal basket and insert the blind basket into the portafilter.
Step 2: Add Cleaning Powder
Add approximately 3–5g of espresso machine cleaning powder into the blind basket.
Step 3: Run the Backflush Cycle
Lock the portafilter into the group head.
Run the pump for 10 seconds.
Stop for 10 seconds.
Repeat this process 4–5 times.
You’ll hear pressure release into the drip tray. This is normal and helps break down internal coffee residue.
Step 4: Rinse Thoroughly
Remove the portafilter, rinse it, and repeat the cycle using clean water only at least 5 times to flush out any remaining cleaner.
Step 5: Clean the Shower Screen and Gasket
For deeper maintenance:
Remove the shower screen if possible
Soak it in hot water with cleaning powder
Scrub gently
Rinse thoroughly before reinstalling
How Often Should You Clean Your Espresso Machine?
Home Espresso Machines
Backflush with water: Daily
Backflush with cleaning powder: Weekly
Commercial Espresso Machines
Backflush with cleaning powder: Daily
Regular cleaning prevents expensive repairs and keeps extraction consistent.
Signs Your Espresso Machine Needs Cleaning
You should clean your espresso machine group head immediately if you notice changes in taste, extraction or performance. A buildup of coffee oils and residue inside the group head can quickly affect flavour quality and water flow, leading to inconsistent espresso and potential wear on internal components. Watch out for the following warning signs:
Bitter, burnt or sour tasting espresso
Thin, weak or patchy crema
Uneven or spluttering espresso flow
Black residue visible on the shower screen
Difficulty locking the portafilter into place
These are all common indicators of coffee oil buildup and signal that your espresso machine needs thorough cleaning and backflushing.
Does Cleaning the Group Head Improve Espresso Taste?
Yes — significantly. Cleaning your espresso machine group head has a direct impact on coffee quality. Old coffee oils turn rancid quickly under heat and pressure, and if they remain inside the group head, they contaminate fresh espresso shots and mute flavour clarity. Regular backflushing with a proper espresso machine cleaning powder removes these residues and restores performance, resulting in:
Cleaner tasting espresso
Improved aroma
Thicker, more stable crema
More consistent extraction
Better flavour balance in every cup
A clean group head doesn’t just protect your machine — it protects the taste of your coffee.
Common Espresso Machine Cleaning Mistakes
Even with good intentions, incorrect cleaning can damage your machine or affect coffee flavour. Proper espresso machine maintenance is essential for both performance and longevity. Avoid these common mistakes when cleaning your group head:
Using washing-up liquid instead of espresso machine cleaning powder
Not rinsing thoroughly after backflushing
Skipping weekly detergent backflushing
Ignoring the group head gasket and shower screen
Backflushing machines that are not designed for it
Using a professional espresso machine cleaning powder and following the correct backflushing method is critical for safe, effective maintenance and consistently great-tasting espresso.
If you want consistently great espresso at home or in a café setting, knowing how to clean your espresso machine group head properly is essential. Regular backflushing with a professional espresso machine cleaning powder such as Puly Caff or Cafiza removes stubborn coffee oils, prevents residue buildup and protects vital internal components from long-term damage.
A clean machine doesn’t just last longer — it produces cleaner, clearer flavour with better crema and more consistent extraction.
