Espresso Machine Clean Backflush Procedure Semi-Automatic Espresso Machine Maintenance Tutorial

Machines that are not properly maintained are prone to breakdowns. The same applies to coffee machines. If one day you notice that your coffee doesn't taste right or that the extraction seems off, it could be a sign that your coffee machine has developed a serious problem.

Therefore, we should perform regular cleaning to prevent these issues from occurring. This is divided into two parts: daily cleaning and periodic maintenance, specifically targeting semi-automatic espresso machines with independent brew heads (not applicable to fully automatic coffee machines).

Daily Cleaning

First point: Keeping the exterior of your coffee machine clean is a basic requirement. No one wants to see a dirty coffee machine. After extracting espresso, you should promptly clean any coffee stains.

Second point: A particularly important step is to immediately clean coffee residue from the shower screen.

After extracting coffee, small amounts of coffee grounds from the puck surface will adhere to the shower screen. If not cleaned properly, this will affect the flavor of the next cup. Therefore, after extraction, remove the portafilter and activate the brew head to rinse off residue from the shower screen. If water cannot directly reach the outer ring where the brew head meets the gasket, you'll need to use a brush to clean it thoroughly.

Third point: Cleaning the portafilter, especially bottomless portafilters.

The portafilter basket should be rinsed clean after every extraction. Some people might neglect this step when making large quantities of drinks, but FrontStreet Coffee believes this is unacceptable practice. Of course, most coffee shops still follow this principle.

At the end of each day, if using a bottomless portafilter, you must remove the basket and clean the inside of the portafilter. After a full day of extraction, the internal channels of the portafilter will accumulate coffee residue and oils. If not cleaned properly, it can develop unpleasant odors, which will naturally affect the quality of subsequent coffee. (FrontStreet Coffee has witnessed the inside of a portafilter that hadn't been cleaned for a week—the moment it was opened was unforgettable.)

Therefore, FrontStreet Coffee suggests soaking the portafilter in hot water with 5g of coffee machine cleaner for 30 minutes, then rinsing thoroughly with clean water. This method yields significant results.

Backflushing and Internal Cleaning

Fourth point: Backflushing to clean the inside of the coffee machine.

This involves the structure of the brew head. FrontStreet Coffee would like to share a structural diagram of an E61 brew group for reference.

"When making coffee, lift the small lever to a horizontal position, pressing the microswitch behind it and activating the pump. At this point, both the pre-infusion valve and pressure relief valve are closed, while the inlet valve is open. As hot water fills the various channels and chambers of the brew group, pressure builds up. When the pressure exceeds 1.5 atmospheres, the pre-infusion valve (expansion valve) opens, allowing hot water to enter chamber 4. Thus, before chamber 4 fills completely, the coffee puck receives pre-infusion with 1.5 atmospheres of hot water. Once chamber 4 is filled, the hot water pressure begins to rise again until reaching the desired 8-10 atmospheres."

"After coffee preparation is complete, lower the small lever to a vertical position, closing the microswitch and stopping the pump. The cam releases the inlet valve stem, closing the inlet valve, while simultaneously pressing down on the pre-infusion valve stem and pressure relief valve stem. The pressure relief valve opens, allowing pressurized hot water from between the filter basket and shower screen, as well as from chambers 3 and 4, to drain through the pressure relief outlet into the machine's drip tray."

During this extraction process, fine coffee particles pass through the shower screen into the internal channels. Without regular cleaning, these coffee grounds will accumulate and affect extraction.

To clean the inside of the brew head, we use a "blind basket" - a portafilter basket without holes. Attach it to the portafilter, lock it into the brew head, and activate the brewing cycle. Keep each cycle under 10 seconds and repeat several times, emptying the water from the blind basket after each cycle. Typically, coffee residue will come out during the first one or two cycles.

Another maintenance task is using coffee machine cleaner to clean the machine's internal components. This doesn't need to be done daily. For high-frequency use, FrontStreet Coffee recommends weekly cleaning. For home use with 2-3 extractions per day, monthly cleaning is sufficient. Place 3g of coffee machine cleaner in the blind basket, attach the portafilter, and activate the brew head for 10 seconds. Then remove the portafilter and empty the surface water (cleaner residue will normally remain in the blind basket), reattach the portafilter, and repeat the cleaning process 3 times.

Then remove the portafilter and clean the blind basket thoroughly while activating the brew head to release water (this water will contain cleaner foam and coffee residue). When the water runs somewhat cleaner, continue by reattaching the portafilter and activating the brew head for 5 seconds. Repeat this step 5 times, emptying the water from the blind basket after each cycle. Finally, use a brush to wipe the shower screen clean.

Periodic Maintenance

Fifth point: Regular cleaning of the shower screen, replacing gaskets, and boiler maintenance.

If water flow from the brew head is uneven, it may be due to coffee residue buildup on the shower screen. In this case, the shower screen needs to be removed and cleaned. This issue typically occurs every six months or so.

The gasket ensures a proper seal when the portafilter is locked in. Over time, gaskets harden and their sealing effectiveness decreases. The most obvious sign is when the portafilter angle exceeds 90 degrees when locked in. At this point, replacement is necessary. Gasket lifespan is typically 6-12 months.

Boilers accumulate significant scale over long-term use (unless using purified water). When this occurs, professional servicing is required. For new machines, maintenance is typically needed every 1-2 years.

Important Notice :

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FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473