Typical errors with portafilter machines: pressure build-up and pressure problems
Coffee from a portafilter machine can be a true taste experience. However, some common brewing mistakes can significantly impact the pressure buildup and thus the quality of the coffee. Typical pressure problems with portafilter machines can be attributed to various factors, both machine-related and related to the coffee preparation.
In this article, we take a look at typical problems and their solutions if your portafilter machine is not building up any or too little pressure.
1. Incorrect grind
Problem: The coffee grind is crucial for pressure buildup. If the coffee is ground too coarsely, the water can pass through too quickly, resulting in weak pressure. Conversely, grinding too finely can clog the portafilter and also negatively affect pressure.
Solution: Experiment with the grind size. A medium-fine grind is usually optimal. Depending on the machine and beans, there may be slight variations, so it's worth trying different grind sizes.
2. Insufficient coffee dosage
Problem: Too little coffee in the portafilter can also lead to insufficient pressure being built up. If the portafilter is only half full, the water won't be properly pressed through the coffee grounds.
Solution: Make sure to weigh the recommended amount of coffee (usually between 18-20 grams for a double espresso) and distribute it evenly in the portafilter.
3. Uneven tamper technique
Problem: Unevenly tamped coffee results in uneven extraction and can disrupt pressure buildup. If certain areas of the coffee are less compressed, water can escape those areas more easily, resulting in poor pressure.
Solution: Use a tamper to evenly pack the coffee grounds. Apply consistent pressure and check that the coffee is evenly distributed in the portafilter chamber.
4. Clogged or dirty components
Problem: Deposits of coffee fat and oils can clog the brewing unit or filter, which can significantly impair pressure build-up.
Solution: Regularly clean your portafilter, nozzle, and all other parts of the machine that come into contact with coffee. Special espresso machine cleaners can be helpful here.
5. Water temperature and pressure
Problem: If the machine does not build up the correct temperature or the required pressure, this can also lead to insufficient pressure.
Solution: Check the machine parameters. Ideally, the water temperature should be between 90-96°C. If your machine has a pressure gauge, ensure the pump pressure is between 9-10 bar.
6. Inappropriate sieve insert
Problem: Using an unsuitable or damaged screen insert can also negatively affect the print.
Solution: Check the filter insert for cracks or damage. Use only genuine replacement parts and filters that fit your machine.
7. Technical problems
Problem: Either the pump in the portafilter machine is no longer working properly, or the solenoid valve is broken. Some models have a so-called level sensor or float switch in the fresh water tank. If this is defective or stuck, the pump may not activate.
Solution: In this case, we advise against DIY measures, as the machine must be opened professionally and the fault analyzed. Often, other hidden defects and subsequent errors occur simultaneously.
