If the coffee machine De'Longhi coffee begins to drip slowly or the stream becomes intermittent, this is a direct signal that the hydraulic balance inside the brewing unit is disturbed. Most often, the problem lies in excessively fine grinding of the grains, which creates excessive resistance to water passing through the compressed tablet. The pressure in the system increases sharply, and instead of a powerful jet, the user observes a rare drip or a complete stop in the flow of the drink.
This phenomenon can be caused not only by grinding settings, but also by simple clogging of the outlet openings of the teapot or scale in the boiler. Hydraulic system Espresso machines are designed to operate at a certain pressure, usually 9 bar, and any downward deviation in flow indicates blockage. Ignoring this symptom often leads to pump overload and premature wear of the seals.
⚠️ Attention: If you hear the hum of the pump, but no coffee comes out, immediately stop the water supply so as not to tear off the O-rings of the brewing unit.
Effect of grinding degree on flow rate
The most common reason why a coffee machine De'Longhi drips slowly, the grinding degree is incorrectly set. When coffee particles are ground too finely, they turn into dense dust, which when pressed into the boiler forms a monolithic mass. Water under pressure cannot quickly pass through this layer, which leads to a slowdown in the spill. Adjusting this parameter is the first step in diagnosis.
To adjust, you need to find the grind regulator, which is usually located inside the bean hopper or on the side of it. By turning the mechanism towards increasing the fraction size (usually indicated by numbers or an arrow), you will reduce water resistance. It is important to carry out this operation only when the millstones are rotating, that is, immediately at the moment the grinding process starts, so as not to damage the adjustment mechanism.
- 🔄 Grinding too fine creates high pressure and slows down the flow.
- 🔄 Coarse grinding speeds up the flow, but can worsen the quality of extraction (cream).
- 🔄 Adjustment should be made in small steps, checking the result after 2-3 cups.
The optimal espresso flow lasts 20-30 seconds. If the time exceeds 40 seconds, you need to make the grind coarser.
Clogged brewing unit and screens
The second most important factor affecting the speed of serving a drink is physical contamination of the internal elements. During operation, coffee oils and small dust particles accumulate on the mesh of the brewing unit and in the water supply channels. Over time, this coating hardens, significantly narrowing the flow area for liquid.
If your model allows you to remove the brewing unit, it is necessary to carry out a visual inspection and mechanical cleaning. Users often forget about the upper mesh (dispenser), through which coffee flows into the cup. This is where old coffee jams most often form. Flushing with warm water without using detergents will help restore normal fluid flow.
☑️ Diagnosis of blockages
| System element | Symptom of pollution | Cleaning method |
|---|---|---|
| Brewing unit | Coffee drips, tablet is dry | Washing with warm water, removing oils |
| Dispenser mesh | Uneven flow, splashes | Mechanical brushing |
| Boiler needle | Weak pressure when supplying boiling water | Decalcification (removal of scale) |
Problem with scale in the hydraulic system
Scale, formed from hard salts contained in tap water, is the hidden enemy of any coffee machine. Calcite deposits accumulate inside the boiler and in the narrow pipes through which hot water is supplied to the brewing unit. Even if the device looks clean on the outside, the internal diameter of the tubing may be reduced by half, which critically reduces the pump's performance.
Regular use of the decalcification program is a mandatory requirement of the instructions De'Longhi. If you haven’t carried out this procedure for a long time or use tap water without a filter, the likelihood that the reason for the slow dripping is scale is close to 100%. A special solvent effectively removes mineral deposits, restoring the permeability of the system.
⚠️ Warning: Never use vinegar or citric acid to descale as they may damage the rubber seals and plastic parts inside the machine.
Malfunctions of the pump and solenoid valve
If adjusting the grind and cleaning did not help, the coffee machine De'Longhi is still dripping slowly, it is worth considering technical faults. The pump (pump) loses its performance over time. The diaphragm inside the pump may wear out or become deformed, which does not allow the required operating pressure of 9-15 bar to be created. As a result, water is simply forced through the coffee by gravity or under minimal pressure.
The solenoid valve that regulates the pressure release may also be the cause. If it is “stuck” in the open position or is partially blocked by scale, part of the pressure is released into the drain, not reaching the brewing chamber. Diagnosis of these components requires disassembling the housing and using a pressure gauge, so without repair skills it is better to contact a service center.
- 🔧 Wear of the pump membrane leads to a drop in pressure.
- 🔧 Sticking of the pressure relief valve reduces the jet pressure.
- 🔧 Oxidation of contacts can cause unstable pump operation.
The influence of coffee variety and freshness
The quality and characteristics of the grain itself also play a role in the flow rate. Old, overdried coffee or beans that have been stored in open conditions for a long time will lose their oils and structure. When grinding, such grains produce a lot of fine fraction (“dust”), which behaves like cement, clogging the filter. This creates the illusion of a machine failure, although the problem lies in the raw material.
On the other hand, beans that are too wet or oily (such as dark roasts with oil oozing out) can clump together in the hopper and burrs, creating an uneven grind. Large pieces and fine dust mixed together can chaotically block the path of water. Using high-quality, fresh, medium-roasted beans often solves the problem without interfering with the equipment settings.
The secret to the perfect espresso
Use blends that contain up to 20-30% robusta. Robusta produces a denser crema and holds pressure better than pure Arabica, which can be too loose.
Self-diagnosis algorithm
Before taking the device for repair, you should perform a sequential algorithm of actions that will allow you to localize the problem. Start with the simplest thing - changing the water and checking the grind, then move on to servicing the brewing unit. A systematic approach will eliminate false diagnoses and save budget.
If after completing all steps the coffee machine De'Longhi It's still dripping slowly and the lights aren't showing any errors, internal components probably need to be replaced. You should not ignore the problem, since operating the pump “pull-in” with a high resistance of the medium can lead to its complete failure.
Main conclusion: In 80% of cases, slow spillage is treated by increasing the degree of grinding and timely decalcification.
Frequently asked questions (FAQ)
Why did the coffee machine start to drip even slower after cleaning?
It is possible that when assembling the brewing unit, the sealing rings were installed incorrectly or the unit itself was misaligned. Also check to see if the mesh holes are clogged with scale residue that fell off during cleaning.
Can I use ground coffee in the De'Longhi if the machine is pouring slowly?
Using ground coffee (via bypass) helps check if the problem is with the grinders. If the flow through the ground coffee is normal, then you need to adjust the grinders or change them. If it drips through the ground, the problem is in the pump or scale.
How often should you change the water filter in your coffee machine?
The standard life of a filter cartridge is about 50 liters or 2 months of use. Failure to replace the filter in a timely manner leads to the system quickly becoming overgrown with scale, which directly affects the rate of spillage.
Does water temperature affect dripping speed?
Indirectly affects. Water that is too hot can dissolve coffee oils faster, creating an emulsion that is less able to pass through the filter. However, the main factor is the physical resistance of the coffee tablet.