Sudden cessation of operation of the refrigeration unit model unit Atlant often becomes an unpleasant surprise, especially when perishable products remain inside. The owner immediately begins to look for the cause, and one of the most difficult but probable diagnoses is clogged capillary tube. This narrow copper connection, less than a millimeter in diameter, serves as a choke where the liquid refrigerant turns into vapor, providing cooling to the chambers.
The symptoms of this malfunction can be deceiving and often resemble compressor problems or a leak Freon. However, if you notice that the motor-compressor runs continuously, hums, but no cold is generated, or one of the chambers (usually the freezer) is covered with snow and the other is warm, you should think about checking the circulation system. In this article we will look in detail at how to diagnose the problem and whether it is possible to clean the capillary at home without a professional station.
⚠️ Attention: Independent intervention in the sealed circuit of the refrigerator requires special tools and skills. Improper evacuation or moisture entering the system will lead to compressor failure and costly repairs.
Before taking active steps, it is necessary to understand the physical essence of the process. The capillary tube in refrigerators Atlant has an extremely small internal cross-section, which makes it vulnerable to any mechanical inclusions. Most often, the blockage is caused not by external contamination, but by oil breakdown products or oxidation inside the system, which over time form a dense plug.
Diagnostics of a blockage in the capillary system
The first step in identifying a malfunction is to carefully monitor the operation of the unit. If the compressor Atlant turns on, runs for hours, but does not turn off, while the condenser (grid at the back) remains barely warm or cold, this is a sure sign of lack of refrigerant circulation. In a normal situation, the grate should be heated evenly over the entire area.
Experienced craftsmen use the tactile inspection method. With the compressor running, gently touch the capillary tube where it enters the freezer or evaporator. If the tube in front of the suspected blockage is hot, and after it is cold (or at room temperature), then the freon flow is blocked. It is also worth paying attention to the filter drier: if it is covered with frost or, conversely, absolutely cold when the engine is running, this indicates hydraulic seal or an ice plug.
For more accurate diagnostics, a pressure gauge station will be required. By connecting a pressure gauge to the process pipe, you can see abnormal pressure behavior. If the capillary is clogged, the suction pressure will rapidly drop into a deep vacuum immediately after the compressor stops or even while it is running if the clog is complete. This happens because the compressor pumps out all the gas from the evaporator, but a new portion does not enter through the clogged capillary.
⚠️ Attention: If, after briefly turning on the compressor, the pressure gauge shows a deep vacuum (the arrow goes to the left below zero), immediately turn off the device. Operating a compressor in vacuum without a suction load can lead to overheating of the windings and interturn short circuits.
It is important to distinguish a blockage from a leak or malfunction of the compressor itself. If there is a leak, there will simply be no pressure in the system, and if the compressor breaks down (for example, the piston group is jammed), it will hum and click the thermal relay, but will not create pressure. The blockage is characterized precisely by the presence of pressure at the discharge and its absence at the suction with a working motor.
Necessary tools and preparation for repair
Repair of refrigerators Atlantassociated with depressurization of the circuit requires a specific set of equipment. You can't just use wrenches and screwdrivers here. You will need a professional or semi-professional tool that will create a vacuum, apply high pressure and efficiently solder copper tubes.
The main tool is vacuum pumpnecessary for removing air and moisture from the system after repair. Without deep evacuation, the remaining moisture will freeze in the capillary during operation, creating a new ice plug, and the repair will go down the drain. A torch for soldering copper pipes is also critical; in domestic conditions, gas burners with a cylinder are often used, but it is better to use oxygen-propane complexes for high-quality heating.
A high-pressure source is required for cleaning. The ideal option is a cylinder with a dry nitrogen reducer that allows you to regulate the pressure to 20-30 atmospheres. The use of automobile compressors or cans of compressed air for purging is often ineffective due to low pressure and the presence of moisture in the air stream, which is strictly unacceptable.
☑️ Tools for cleaning the capillary
Don't forget to prepare consumables. You will definitely need a new filter drier, since the old one, after depressurization and purging, loses its properties and must be replaced. You will also need solder (silver or copper-phosphorus) and flux if you use copper-phosphorus solder without silver content.
Methods for cleaning a capillary tube
There are several ways to clear a blockage, the effectiveness of which depends on the nature of the plug. The most common and safest method for the system is nitrogen purge under high pressure. To do this, the system is sealed and nitrogen is supplied to the process pipe. The pressure is created short-term but powerful, which often allows you to break through an oily or paraffin plug.
If simple purge does not help, the flushing method is used. A special solvent for refrigeration systems, for example R141b or isopropyl alcohol, is poured into the system through a filter drier (or instead of it). After soaking for several hours, the system is again purged with nitrogen. The solvent softens the deposits, and they are washed out by the gas flow.
In the most difficult cases, when the blockage is caused by copper oxides or oil combustion products after the compressor overheats, mechanical cleaning may be impossible. Then the method of “burning out” or replacing a section of the tube is used. However, the most radical and reliable method remains complete replacement of the capillary tube with a new one, selected in length and diameter corresponding to the model Atlant.
⚠️ Attention: Never use acetone or gasoline to flush the system “Galoshes” or other aggressive solvents that leave an oily residue or do not evaporate completely. This will lead to a chemical reaction with the compressor oil and re-clogging.
It is worth noting that when flushing with a solvent, it is necessary to thoroughly dry the system with a vacuum pump. Residual solvent in liquid form entering the compressor can change the viscosity of the oil or cause water hammer. Therefore, the vacuum stage after washing should last at least 30-40 minutes.
Technology for replacing the filter-drier and capillary
In most cases, cleaning the old capillary is a temporary measure. If a blockage has once formed in the system, there is a high probability of its reoccurrence. Therefore, experts recommend that when opening the circuit, immediately install a filter-drier. This guarantees long-term operation of the refrigerator replacement of the capillary tube and filter drier. This guarantees long-term operation of the refrigerator Atlant.
The process begins with carefully soldering the old capillary from the condenser and entering the evaporator. It is important not to damage the thin evaporator tubes, which are often made of aluminum and easily melt. The new capillary is selected strictly according to the internal diameter (usually 0.6–0.9 mm) and length (from 2 to 4 meters), since these parameters determine the performance of the system.
The filter drier is installed directly in front of the capillary. Its task is to retain moisture and microscopic particles of debris. When soldering the filter, it is important to follow the flow direction indicated by the arrow on the housing and not to overheat it, so as not to damage the adsorbent inside. Soldering should be done quickly, using a damp cloth to cool the filter housing.
| Parameter | Standard value | Influence on the system |
|---|---|---|
| Capillary diameter | 0.6 - 0.9 mm | Determines the freon throughput |
| Tube length | 2000 - 4000 mm | Influences the pressure of condensation and evaporation |
| Nitrogen pressure | 15 - 30 atm. | Necessary for high-quality purging |
| Evacuation time | 30 - 60 minutes | Guarantees removal of moisture and air |
After installing new elements, the system is sealed and tested for tightness with nitrogen (pressure testing) and only then vacuumed. Refrigerant charging is carried out strictly according to the weight indicated on the refrigerator nameplate, using electronic scales.
Checking tightness and charging with refrigerant
After cleaning or replacing tubes, it is critical to make sure there are no leaks. To do this, the system is supplied nitrogen at a pressure of about 10-12 atmospheres. Places of soldering and joints are generously lubricated with soap solution. The appearance of bubbles will indicate a defect that must be eliminated before evacuation begins.
It is recommended to leave the pressure test for several hours (ideally for a day) to make sure that the pressure does not drop. If the pressure gauge holds the arrow, you can start vacuuming. This process removes air and water vapor from the circuit, which at low temperatures would turn into ice and clog the system again.
Filling the refrigerator Atlant is carried out with the liquid phase of freon (usually R600a or R134a) through a filter drier or a special valve. The amount of refrigerant must be correct: underfilling will lead to poor cooling capacity, and overfilling will lead to increased pressure and possible water hammer in the compressor.
Why can't you refill "by eye"?
The amount of refrigerant in modern refrigerators is calculated in grams (usually 50-100 grams). A deviation of even 10-15 grams disrupts the thermodynamic cycle, due to which the compressor operates with overload, and the temperature in the chambers does not drop to the required values.
After refueling, it is necessary to solder the filling fitting and check the operation of the unit in test mode. The compressor should gain temperature, the evaporator should be evenly covered with frost, and the condenser should warm up. The on and off cycles must correspond to the settings of the thermostat.
Typical mistakes during self-repair
Independent repair of refrigeration equipment often leads to aggravation of the situation. One of the most common mistakes is trying to clean the capillary by simply “pumping” the system with a compressor in the opposite direction or using a car pump. This is not only ineffective, but also dangerousas moisture and dirt are driven into the system.
Another common mistake is ignoring the replacement of the filter drier. Many craftsmen, having cleaned the capillary with nitrogen, solder the old filter back. This guarantees re-clogging in the near future, since the resource of the sorbent in the filter is limited, and after contact with the atmosphere it is saturated with moisture.
Incorrect selection of the length of the capillary tube is also common. Installing a tube that is too short or too wide will cause liquid freon to flow into the compressor, causing it to break. Installation that is too long or narrow leads to a lack of cold and overheating of the motor.
⚠️ Attention: Technical characteristics of refrigerators may vary depending on the year of manufacture and the specific model. Always check the technical documentation or markings on the nameplate of your device before ordering parts.
Do not forget about safety precautions when working with open flames and gas under pressure. Cylinders with freon and nitrogen are under high pressure, and freon, when in contact with an open fire, releases toxic substances (phosgene). Work should be carried out in a well-ventilated area.
Prevention and maintenance of the system
To avoid re-formation of blockages in the capillary tube of the refrigerator Atlant, it is important to monitor the condition of the compressor. It is the products of oil aging and wear of the piston group that are the main source of system contamination. At the first signs of unstable operation of the compressor, it is better to replace it than to risk clogging the new capillary.
Regular defrosting of the refrigerator (if it is not a No Frost model) also helps maintain a stable temperature and reduces the load on the unit. Although this has little direct effect on the capillary, the overall healthy microclimate inside the chambers prolongs the life of all components.
If you notice that the refrigerator has begun to work longer than usual or to make noise, do not ignore these signals. Early diagnosis allows you to eliminate the problem at the stage when only adjustment or minor repairs are required, and not a complex operation of flushing the system and replacing expensive components.
Compliance with repair technology and the use of high-quality spare parts is the key to successful restoration of the refrigerator. Do not skimp on tools and materials, as the cost of repeated repairs with replacement of the compressor will be much higher.
Frequently asked questions (FAQ)
Is it possible to blow out the capillary with a regular car pump?
No, this is categorically not recommended. A car pump creates insufficient pressure (maximum 2-3 atm) to break through a dense blockage, and most importantly, it forces moisture and oil from the pump cylinders into the system. The moisture will freeze in the capillary, and the oil will mix with freon, forming a new plug.
How much does it cost to replace a capillary tube in the service?
The cost depends on the region and model of the refrigerator, but the work of replacing the capillary, filter and refilling with freon usually costs from 3000 to 6000 rubles excluding the cost of spare parts. Self-repair may be cheaper, but requires the purchase of expensive equipment.
Why does the refrigerator freeze in only one corner after cleaning?
This may indicate incomplete cleaning, the presence of an “air lock” in the system, or an incorrect length of the installed capillary. It is also possible that there is too much oil or moisture left in the system, which interferes with the normal circulation of the refrigerant.
Is it necessary to flush the system if the compressor burns out?
Yes, definitely. When the compressor windings burn, combustion products and acidic compounds enter the system. If they are not washed with a special solvent and purged with nitrogen, the new compressor will fail in a few months or even weeks.
What kind of freon is used in Atlant refrigerators?
In modern models, isobutane (R600a) is most often used, in older models - freon R134a. The type of refrigerant and its amount (in grams) are always indicated on the factory sticker located inside the refrigerator compartment or on the back wall.