The situation when a coffee machine sucked in the air is one of the most common problems faced by owners of automatic and carbohydrate espresso machines. This usually occurs after a long period of equipment downtime, replacement of filters or when the water tank completely ran out of liquid and the pump continued its work. Instead of supplying water under pressure, the device begins to emit a characteristic buzzing or whistling sound, and from the group, instead of a saturated espresso, only foam or rare drops drip.
The main danger of this condition lies not so much in the absence of coffee in the morning, but in the risk to the pump itself. Many models are equipped with vortex pumps that use water to lubricate and cool rubbing parts. Dry running or pumping of air-water mixture can lead to overheating of mechanism, deformation of seals and, ultimately, to expensive repairs. Therefore, if you notice that the coffee machine sucked in the air, you must immediately stop brewing attempts and begin the procedure for removing the air plug.
In this guide, we will discuss in detail the physical causes of suffocation, algorithms of actions for different types of techniques and methods of prevention. You will learn how to properly use a syringe to pump the system, why it is important to monitor the water level and what mistakes users most often make when trying to restore the device. A proper understanding of the processes that take place inside boiler and hydraulic circuit, will help you avoid panic and quickly return the equipment to working condition.
Causes of suffocation of the hydraulic system
Understanding the reasons why a coffee machine sucks in air is the first step to successfully solving the problem. The main mechanism of air traffic jams is associated with a violation of the tightness of the suction tract or a critical decrease in the level of liquid in the tank. When water becomes scarce, the pump begins to capture air bubbles, which then enter the tube system. Because air is compressed, unlike water, it creates resistance that the pump cannot always overcome, which leads to a stoppage of the fluid supply.
Often the problem lies in the design features or condition of consumables. For example, if snatch-tube inside the tank cracked or loosely adjacent to the pump, the system will constantly suck air even with a full tank. Also, the cause can be clogging of the inlet filter or lime plaque on the valves, which disrupts the normal flow of fluid. In some cases, especially after replacing the softener filter, users forget to pre-soak the cartridge, which leads to intensive emission of gas bubbles from the filter itself.
⚠️ Warning: Prolonged operation of the pump "dry" or with a lot of air can lead to melting of the plastic elements of the pump and failure of the control electronics.
Another factor is the water temperature. If you add cold water to the heated system or vice versa, a sharp temperature drop can provoke cavitation and the formation of steam stoppers that behave similarly to air. In addition, the use of too soft or distilled water sometimes changes its physical properties, contributing to the formation of foam and making it difficult to work. venturist- systems in cappuccinators.
Diagnosis: How to understand that the air in the system
To determine that the coffee machine is suffocated, you can by a number of characteristic signs that manifest themselves both visually and by ear. The first and most obvious symptom is a change in the sound of the device. The normal hum of the pump is replaced by a higher, whistling or intermittent sound. This indicates that the impeller of the pump rotates in a mixture of gas and liquid, creating an acoustic resonance. If your equipment is equipped with a pressure gauge, the arrow will shake or not rise to a working pressure of 9 bar.
Visual diagnosis also provides clear answers. When trying to spill water or make coffee from the group instead of a dense stream will come out intermittent flow with a large number of large bubbles or just steam. The cappuccinator in this situation will stop collecting milk, since the principle of the tube Venturi It is based on creating a vacuum by the flow of steam or water, and the air traffic jam blocks this process. On the display of modern models, the indication “Fill the water tank” can light up, even if it is full.
For accurate diagnosis, it is recommended to perform a few simple actions:
- 🔍 Remove the water tank and check if the intake tube is fully submerged and if there are no cracks at its end.
- 💧 Pour the water to the maximum mark and sway the tank to see if bubbles from the compounds are rising.
- 👂 Apply your ear to the body: the intermittent noise of the pump is a sure sign of a lack of fluid or the presence of traffic jams.
It is important to distinguish suffocation from other malfunctions, such as clogging of the group needle or breaking the pump itself. If the pump is buzzing very loud and heavy, but the water is not going at all, it may be a problem in salt deposition or mechanical blocking. However, if the sound is “bubbling” and variable, it’s almost guaranteed air in the system.
Basic method: air removal through the tank
The easiest and safest way, if the coffee machine sucked in the air, is to create conditions for self-exit bubbles. This method is suitable for most household models with a fixed tank or easily removable container. The essence of the method is to provide the pump with a liquid under a slight excess pressure, displacing the gas from the system.
First, you need to completely remove the water tank. Wash it thoroughly, paying special attention to the bottom where contamination may have accumulated. Recharge fresh cold water to the maximum level. Before installing the tank back on the machine, it is recommended to shake it vigorously several times to remove large bubbles that could have formed during the filling. Place the tank in place and make sure it is firmly up and before the click.
☑️ Pre-pumping check
Now we move on to the pumping procedure. Turn on the coffee machine and wait for the heating cycle to finish. Without starting the coffee preparation, open the hot water or steam tap (if the design permits). Keep it open until a stable stream of water goes out of the nose without “spitting” and bubbles. If your model does not have an external tap, start the cycle of making espresso without coffee (splintering water). Repeat the procedure 2-3 times. Usually 15-20 seconds of pump operation is enough to push the air traffic jam.
In some cases, it helps to lightly tap on the tank or tubes during the pump operation. Vibration helps to separate small air bubbles from the walls of the hoses and combine them into larger ones that are more easily pushed out by pressure. If after three or four cycles of the strait, the situation has not changed and the coffee machine is still sucking in the air, move on to more radical methods.
Syringe method: forced pumping pumping
If standard methods have not helped and the machine continues to suffocate, more serious intervention will be required using a medical syringe of 20 ml or more. This method is the “gold standard” for service engineers and allows you to create high local pressure directly at the pump entrance, forcibly pushing the air traffic jam.
To implement this method, you will need to remove a tank of water. Find the water inlet at the bottom of the tank or on the body of the machine itself (depending on the design). You need to create a sealed connection between the water-filled syringe and the inlet valve. In some models, it is necessary to remove the tank cover or use adapters. The point is to put water under pressure directly into the pump, bypassing the limitations of gravity.
Algorithm of action:1. Get a full syringe of warm water.
2. Tightly press the nose of the syringe to the water entrance to the pump.
3. Turn on the car (strait mode or steam).
4. Press hard and hard on the piston of the syringe.
5. Repeat 3-5 times until a smooth stream appears.
The key here is synchronization. Pressure on the piston is necessary at the moment when the pump is turned on. The pressure of the syringe water should be higher than the resistance of the air plug. It is critically important to use warm water (about 40-50 degrees), since cold water can cause thermal shock in the heated elements of the boiler, and hot water can damage the rubber seals of the syringe.
⚠️ Warning: When working with a removed tank, be careful not to spill water on the electrical contacts and control board. Use dry wipes and act carefully.
After successful pumping, collect the structure back, pour a full tank and make several idle straits to stabilize the pressure. This method is effective in 95% of cases when the coffee machine sucked in air and stopped pumping water.
Features for different types of coffee machines
The process of air removal can vary significantly depending on the type of device you have. Owners of carob (carob) coffee machines, such as DeLonghi EC or BrevilleThey often experience suffocation after replacing the softener filter. In such models, it is important to pre-soak the filter in water for 5-10 minutes so that it is saturated with moisture and stops releasing air bubbles into the system.
Automatic coffee machines with intake tube (for example, some models) Saeco or Siemens with an external tank) require special attention to the condition of the silicone tube. If it is dry or cracked, it will constantly suck air. In such cases, no pumping will not help - a replacement tube is required. Capsule machines, such as NespressoThey often have built-in systems that self-removal air when first turned on, but if the cork is severe, it may be necessary to spill water repeatedly without the capsule.
| Type of coffee machine | Probability of strangulation | Specificity of removal | Risk to the pump |
|---|---|---|---|
| Carrot (without boiler) | Tall. | Strait through the vapor nose | Medium. |
| Automatic (with boiler) | Medium | Service menu/Syringe | High-pitched |
| Capsule | Low. | Multiple strait | Low. |
| Professional (2 pumps) | Medium | Plum through the group | High-pitched |
For professional machines with two pumps (one for coffee, one for steam), the situation can be more complicated. You may need to release pressure in the system through safety-valve before the start of the pumping procedure. Always check the specific model instructions as the valve location and access varies greatly.
Prevention and maintenance
To make sure that the coffee machine never sucks air again, you need to adhere to simple rules of operation. The main rule is not to allow complete emptying of the tank during operation. Modern machines have level sensors, but rely on them completely is not worth it. As soon as the water level has dropped below the minimum level, immediately add liquid. This will prevent air capture by the intake tube.
Regularly check the condition of the filter-mesh at the bottom of the tank. If it is clogged with scale or mucus, the flow of water becomes difficult, and the pump begins to work with overload, creating zones of thinning where bubbles form. Cleaning the tank once a week with warm water with a mild detergent will help maintain hygiene and normal hydraulics.
The myth of distilled water
Many people believe that using distilled water will save you from scale, but this is not true. The distillate can aggressively affect the metal parts of the boiler and contribute to corrosion, and also conducts current worse, which knocks down water level sensors in some models. It is better to use filtered water of medium hardness.
It is also important to monitor the temperature. Do not leave your car on standby for days if you are not using it. Constant cycles of heating and cooling contribute to the formation of micro-bubbles. If you plan a long break in use, drain water from the tank and boiler (if the design allows) and store the machine in a dry form.
To check the tightness of the system, lubricate the places of connections of the tubes with soap solution. If the pump appears bubbles in the system there is an air sucker that requires replacement of seals.
When needing professional help
Although most cases of suffocation are solved on their own, there are situations where the coffee machine sucked the air due to a more serious breakdown. If after all the pumping procedures, using a syringe and checking the tubes the problem persists, the pump itself may have failed. Whirlwind pumps have a limited resource, and with prolonged work "on dry" their impeller can be deformed, because of which they lose the ability to create the necessary pressure and self-suction.
Also, the cause may be a malfunction of the electromagnetic valve or water flow sensor. If the valve is stuck in the closed position, the water will not physically be able to pass further, creating the illusion of an air traffic jam. In complex automatic machines with electronic control, software failures may occur that require flashing or resetting errors through the service menu, which is better to trust professionals.
⚠️ Attention: Independent disassembly of the pump or boiler can lead to loss of warranty and violation of the tightness of the high-pressure system. If you are not sure of your abilities, contact the service center.
It is worth contacting the master if you hear the smell of burning, see sparkling or if the machine emits an unnaturally loud grinding. These are signs that the problem has gone beyond mere suffocation to involve mechanical or electrical components. Timely repairs will be cheaper than replacing a burnt boiler or pump.
If after 5-7 cycles of pumping with a syringe, the water did not go smoothly, mechanical failure of the pump or valve is likely, requiring replacement of parts.
Frequently Asked Questions (FAQ)
Can I turn on a coffee machine without water in the cleaning tank?
Absolutely not. Turning on the pump without water leads to dry friction, overheating and rapid failure of the pump. Always make sure the tank is full before running any wash or spill cycles.
Why does a coffee machine hum, but not make coffee, even though there is water?
Most likely, there was an air traffic jam in the pump or the inlet filter clogged. It is also possible that the group's needle is clogged with coffee oils. Try the syringe pumping method or reverse washing.
How often should I change the water in the tank to avoid problems?
It is recommended to change the water daily, especially if the machine is not actively used. Stagnant water loses its properties, bacteria multiply in it and the gas composition changes, which can contribute to the formation of traffic jams.
Will vacuuming the tank help if the machine sucks in air?
No, vacuuming of the tank is not required and can be dangerous for the design of plastic containers. The pump itself creates the pressure in the system, your task is simply to ensure unhindered access of the liquid to the pump.
What if the water flows after pumping?
These are residual phenomena. Continue the water spill (2-3 full tanks) through the system. The air bubbles will gradually dissolve or exit and the flow will stabilize. If the jerks persist for a long time, check the tightness of the connections.