The situation when coffee-pill after the strait is wet, porridgeous or, conversely, dry and crumbly, familiar to many owners of automatic coffee machines. This is not just a minor nuisance, but a direct signal of a violation of the technological process of brewing. Normally, the compressed cake should retain the shape of the "puck", be moderately wet and easily separate from the walls of the brewing block. If you find slurry in the container or, worse, the residue of coffee in the brewing module, this requires immediate intervention.
The reasons for this behavior of the device can be several: from banal non-compliance with hygiene to serious breakdown of the grinding mechanism or dosing system. Crumb pill Often indicates that the grinding is too large, and the water pressure is not enough to form a dense layer. At the same time, excessively wet cake may indicate problems with pressure or sealing. Understanding the physics of the process will help you quickly identify the root of the problem.
In this article, we will analyze in detail the mechanics of the brewing unit, consider typical user errors in the maintenance of equipment and provide a step-by-step diagnostic algorithm. Grinding adjustment Proper cleaning is key, but sometimes it requires replacement of worn parts. Do not ignore the first symptoms, as working with improperly prepared coffee can lead to clogging of the hydraulic system and failure of expensive nodes.
The Perfect Brewing Mechanics: How It Should Work
To understand why. coffee-pill It is necessary to clearly represent the ideal cycle of the coffee machine. The process begins with grinding the grains: the millstones must grind them to a small fraction resembling powdered sugar. Then the auger serves ground coffee in the dosing chamber, where the portion mechanism measures a strictly defined number of grams. This stage is critically important. grinding-consistency.
After dosing, a brewing block enters the case. Its pistons compress coffee under high pressure, forming a tight "puck." Through this compressed layer, hot water with a temperature of about 90-95 degrees is supplied. The pressure in the system can reach 9-15 bar. If all the parameters are met, the water evenly passes through the thickness of the coffee, extracting the taste and aroma, and at the exit we get a dense, whole cake.
However, if the balance between particle size, water amount and compression force is disturbed, the structure of the tablet is destroyed. Crumb cake The water passed too quickly without resistance. Wet porridge is a sign that the water has either not been squeezed or the compression pressure was not sufficient to hold the shape. It is important to monitor these nuances visually with each pallet cleaning.
⚠️ Warning: If you regularly see coffee slime instead of formed tablets in the pallet, stop using the machine in espresso mode immediately. Working in this mode can lead to the entry of large particles of coffee into the hydraulic system and boiler, which will cause expensive repairs.
Diagnosing grinding problems: size matters
The most common reason why coffee-pill It is broken down or turns out too loose, lies in the settings of the millstones. Many users forget that the properties of coffee beans vary depending on the variety, degree of roasting and even the humidity of the air. If the grinding is too large, the coffee particles cannot cling to each other under water pressure.
As a result, water passes through the layer of coffee almost unimpeded. This phenomenon is called “underextraction”. Coffee turns sour, watery, and the tablet is dry and brittle. Conversely, if the grinding is excessively fine, the machine may hum trying to push the water through, and the pill will be burnt and bitter, albeit dense. Adjustment should be made only during the operation of the coffee grinder.
For correction, you need to find a regulator on the millstones (usually marked with numbers or divisions). Turning to lower values (1-2-3) grinds smaller, increasing resistance. The turn towards greater values (6-7-8- Bigger. The changes will only take effect after 2-3 cups are prepared, as the old coffee remains in the system.
It is also worth considering that old or dull millstones can not give a uniform grinding. In the mixture will be present and large dust, and large pieces. This diversity leads to the fact that coffee-pill It is structurally unstable: it can be dense at the edges and liquid in the center. Check the millstones for chipping and wear.
Problems of dosing and operation of the brewing block
If everything is in order with grinding, attention should be switched to the mechanics of the brewing node. This is where the pill is formed. The main element here is a dispenser that pours coffee into the chamber. If the mechanism is knocked down or contaminated, the amount of coffee served may not be sufficient. Little coffee - the tablet is thin, can not withstand pressure and falls apart.
The second important aspect is the purity and lubrication of the brewing block. On the ossifying rings of pistons over time, coffee oils and plaque accumulate. This causes the pistons to not be able to press tightly against each other or against the walls of the chamber. Microgaps are formed through which water and coffee flow. As a result, you get pill-pod and the dirt around the block.
The third factor is the wear of the springs or the pistons themselves. In some models of coffee machines (for example, DeLonghi or Saeco) the pressure force weakens over time. The mechanism simply cannot create enough pressure to form a tight puck. In this case, it is necessary to replace worn parts or the entire welding module.
☑️ Diagnosis of the brewing block
Do not forget about the system of resetting the pill. If the ejection mechanism is not working properly, part of the cake may remain in the chamber. In the next cycle, old, already used porridge is mixed with fresh coffee. This is guaranteed to result in the new coffee-house The portion will not form correctly and will turn into a formless mass.
Effects of coffee variety and degree of roasting
Often users look for a breakdown where there is only a feature of the raw material. Different types of coffee behave differently in the coffee machine. For example, light roast grains (Scandinavian, cinnamon) are more hard and dry. They are worse pressed and give more pillIt's better than dark roasting. Dark roasting contains more oils that act as a binder.
Robusta and Arabica also have different densities. Robusta is more hard and gives a denser, but less porous tablet. Arabica is softer. If you have changed the coffee in the bunker without setting the machine, the result will be unpredictable. Perhaps the current grinding settings just aren't suitable for new grains.
The freshness factor is also critical. Coffee that has been roasted for more than 6 months loses most of its gases and oils. This “dead” coffee is almost impossible to compress into a normal tablet, even on the perfect equipment. It will behave like inert dust. Using fresh grains (optimally 2-4 weeks after roasting) improves the situation significantly.
The secret of the mixture for the perfect pill
To obtain a stable tablet, professionals recommend using mixtures with a Robusta content of at least 10-20%. Robusta contains more gum and oils, which improves the binding properties of coffee dust when pressed. Pure Arabica light roast will always give a looser cake.
Diagnostic table: symptom and solution
For quick identification of the problem, use the following table. It will help to compare the appearance of the cake with the likely cause of the malfunction.
| Kind of coffee pill | Probable cause | Action. |
|---|---|---|
| Dry, crumbles into dust | Too big a grind. | Reduce the grinding number (make smaller) |
| Wet, mushy, slime | Insufficient pressure or little coffee | Check the dispenser, clean the brewing block |
| Tight, but cracked. | Uneven grinding or old coffee | Replace grain, check the millstone |
| Very dark, burnt. | Too small a grind | Increase the grinding number (make it bigger) |
| The water layer above the pill | Clogged drain system or overflowing pallet | Clean the drainage system, pour water out of the pallet |
Analyzing the state of the cake regularly, you can prevent serious breakdowns. For example, if you notice that the pill has suddenly changed even though you haven’t changed the settings, it could indicate wear on the millstones or contamination of water level sensors.
Hygiene and maintenance: prevention of problems
Regular maintenance is the key to a long life of the coffee machine and stable quality of coffee. Coffee pill Often suffers from a banal lack of cleanliness. Oils, oxidized in air, turn into a sticky substance that interferes with the work of mechanisms. Washing the brewing unit with warm water (without detergents) should be carried out weekly.
Once every 2-3 months, it is necessary to decalcinate (scaling removal). Scale affects the work of the boiler and thermoblock, which can indirectly affect the temperature of the water and, as a result, the viscosity of coffee oils. Cold water extracts coffee worse, which also changes the structure of the tablet.
Wipe the brewing unit dry before installing it back into the car. Residual moisture on the outside of the unit can get onto electrical contacts or sensors, causing electronic errors that the user may mistake for mechanical failure.
Also check the condition of the filters in the water bunker and in the water intake system. If the filter is clogged, the pump is overloaded, the pressure in the system drops, and water cannot pass through the compressed coffee at the desired speed. This causes the cycle to break prematurely and the tablet to remain wet.
⚠️ Warning: Never use aggressive chemicals, dishwashers or hot water above 60 degrees to wash your brewing unit. The plastic can be deformed, and the lubricant from the seals will be washed away, which will lead to leaks and creaking.
When a Master's Challenge is Required
There are a number of situations where self-configuration will not help. If after cleaning, decalcination and adjustment of grinding coffee-pill It is still not formed, the problem may be deeper. For example, a pump (pump) that does not create the desired pressure of 9 bar has failed. Or the TEN died and the water is not hot enough.
Another complex breakdown is a violation of the calibration of pressure or water level sensors. Electronics think the process is complete and stops supplying water ahead of time, or, conversely, delivers too much water. Diagnosis of such malfunctions requires special equipment (manometer, tester).
If the adjustment of the grind in extreme positions does not change the consistency of the coffee and the type of tablet, then the mechanical part of the grinder is faulty or a replacement of the brewing unit is required.
It is also worth contacting the service if you hear foreign knocks, gnashing or hum while working. This may mean that a foreign object has hit the millstone or bearings have broken. Operating the machine in this state will lead to the complete destruction of the coffee grinder.
Sometimes the problem lies in the electronic control module. If the machine’s “brains” fail, they may mismanage the water supply valves. In this case, the tablet can be of any shape, and the machine itself can give out errors on the display or flash indicators for no apparent reason.
Why does the pill stick to the top piston and not fall into the dump?
This is a common problem associated with excessive humidity or too fine grinding. When coffee is ground into dust, it turns into a sticky mass when brewed. When the upper piston rises, this mass reaches for it. Solution: make the grind a little bigger and make sure the piston seals are clean and lubricated with food lubricant.
Can I use ground coffee in an automatic machine?
Only through a special bypass dispenser (bypass), if it is provided by the model. Sprinkling ground coffee in the bean bin is CATEGORICALLY PROHIBITED. This will cause the grindings to break and the screw to jam. For ground coffee, you need to choose the appropriate mode, where the machine misses the grinding stage.
How often should I change the water in the tank to maintain the quality of the pill?
The water in the tank is recommended to be changed daily, even if it is not finished. Stagnant water loses oxygen, which negatively affects the taste of coffee. In addition, bacteria multiply faster in standing water, which can clog thin tubes of the hydraulic system, disrupting the pressure and formation of the tablet.
Does the hardness of water affect the density of the coffee tablet?
Yes, indirectly. Hard water forms scale faster, which narrows the diameter of the tubes and holes in the brewing block. This changes the hydraulic resistance of the system. In addition, the mineral composition of water affects extraction: too soft water can give an acidic taste and loose structure, too hard – bitter.
What if the machine stopped forming the pill after cleaning?
You may have washed all the factory lubricant off the seals, and now the pistons don't provide tightness. Or you have not assembled the block incorrectly. Take it apart again, check the position of the springs and sealing rings. If necessary, apply special food lubricant to rubber seals.