Owners of refrigeration equipment Indesit often face a situation where the compressor runs continuously, hums, but no cold appears inside the chamber. In 80% of such cases, the problem lies in a blockage capillary tube, which is the “bottleneck” of the entire refrigeration system. The refrigerant cannot circulate through the circuit, and the cooling process stops, although the motor is working.
Cleaning the capillary tube of the Indesit refrigerator at home is a complex task, requiring specific tools and skills in working with metal. This is not just flushing, but a full-fledged one associated with depressurization of the system, the use of nitrogen under pressure and subsequent evacuation. Without completing these steps, refilling with freon is impossible. refrigeration circuit repair, associated with depressurization of the system, the use of nitrogen under pressure and subsequent evacuation. Without completing these steps, refilling with freon is impossible.
This article describes in detail the technological process of removing the blockage, the necessary tools and safety measures. It is important to understandthat intervention in the refrigerant circulation system requires caution: the pressure in the circuit can be dangerous, and the use of open flame when soldering, it requires compliance with fire safety.
Diagnostics of a clogged capillary system
Before you start disassembling and cleaning, you need to make sure that the problem is in the capillary. Symptoms may be similar to a freon leak or compressor failure. The main symptom is the nature of the motor: it turns on, runs for a long time, trying to gain temperature, but refrigerator compartment remains warm. In this case, the compressor itself may be hot, and the condenser (grid at the back) may be only partially cold or warm.
The second diagnostic method is tactile. With the compressor running, run your hand along the capillary tube (the thin copper tube that runs from the filter drier to the evaporator). Normally, it should be warm after the filter and gradually cool down. If you feel a sharp temperature change or the tube is cold only at the very entrance to the evaporator, and then warm - this is a sure sign hydraulic resistance due to a plug.
⚠️ Attention: Before any diagnostics, be sure to disconnect the refrigerator from the power supply! Working with electrical components and soldering require a complete absence of mains voltage.
It is also worth paying attention to the filter drier. If it is swollen or shows traces of oil on its surface, this confirms that there is high pressure in the system caused by a blockage. Often, a blockage is formed due to the oxidation of oil that entered the system during previous repairs, or due to moisture, which turned into an ice plug in the low temperature zone.
Necessary tools and materials
For high-quality work on cleaning the capillary tube of the refrigerator Indesit a regular set of household tools will be not enough. You will need specialized equipment that ensures the process is tight and safe. Without a nitrogen cylinder and a vacuum pump, it will not be possible to carry out high-quality repairs, since simple blowing with your mouth or a compressor will not remove moisture and microscopic particles.
The main list of equipment includes a torch with solder (phosphorus or silver), a pipe cutter, a rolling tool (if you need to replace sections of tubes) and a pressure gauge station. A critical element is a cylinder with technical nitrogenwhich is used to purge the system and create excess pressure during soldering, preventing oxidation of copper from the inside.
- 🛠️ Soldering kit: torch, solder, flux (for joining copper tubes).
- 💨 Cylinder with nitrogen and reducer (for purging and pressure testing).
- 🔌 Vacuum pump (to remove air and moisture from the circuit).
- ⚗️ Refrigerant (freon R600a or R134a depending on models Indesit).
Don't forget to prepare a new filter drier. The old element, after depressurization of the system and contact with atmospheric air, loses its properties and must be replaced. You will also need tools for cleaning the pipes: a file or a special cup countersink.
Nitrogen purging technology and removal of plugs
The cleaning process begins with dismantling the compressor and access to the capillary tube. After unsoldering the condenser and evaporator from the filter-drier, it is necessary. blow through each circuit separately. The capillary tube has a very small diameter (about 0.6–0.9 mm), so the plug can be very dense. Blowing is carried out with compressed nitrogen under pressure up to 10–12 atmospheres.
If nitrogen does not pass through the capillary, the method is used. “pushing.” The tube is silenced on one side, and high pressure is applied on the other. Sometimes it helps to briefly block the outlet while the gas supply continues, which creates a hydraulic shock that breaks the oil plug. In difficult cases, the tube must be heated with a burner to soften the frozen oil, but this must be done extremely carefully so as not to burn out the copper.
⚠️ Attention: It is strictly prohibited. blow the system with oxygen or air from a compressor with oil! Oxygen mixed with oil and freon forms an explosive mixture, and the air contains moisture, which will cause a new blockage in a short time.
The table below shows the main parameters of the system elements for different types of refrigerants used in refrigerators Indesit:
| Parameter | R600a (Isobutane) | R134a (Freon) |
|---|---|---|
| Oil type | Synthetic (POE) | Mineral or Synthetic |
| Purge pressure | 10-12 atm. | 12-15 atm. |
| Capillary diameter | 0.6 - 0.8 mm | 0.7 - 0.9 mm |
| Capillary length | 3.5 - 5 meters | 2.5 - 4 meters |
After successful purging of all lines, when nitrogen passes freely through the system, it is necessary to reassemble the circuit, installing a new filter drier. Only after this can you start vacuuming.
☑️ Algorithm for cleaning the capillary
Replacing the filter drier and vacuuming
The filter drier is a critical unit that retains moisture and oil breakdown products. When opening the system, it instantly absorbs moisture from the air, so the packaged new filter is opened only at the time of installation. In refrigerators Indesit filters with a copper body are often used, which are soldered into the gap between the condenser and the capillary tube.
The soldering process requires speed and accuracy. The burner flame is directed to the joint, heating the pipe evenly. The solder must melt from the heat of the pipe, and not from the fire of the burner. After installing the filter, it must be carried out. procedure vacuuming. This is a stage that is often neglected by amateurs, but it is this that determines the durability of the repair. The vacuum pump removes air and water vapor from the system, lowering the pressure to a value at which water boils at room temperature and evaporates.
Vacuum pump operating time. should be at least 30–40 minutes for a system with a capillary tube. The pressure gauge should show a pressure close to -1 bar (or -760 mm Hg). If, after closing the valve and turning off the pump, the pressure gauge arrow creeps up, then there is a leakage in the system (microcrack or poor soldering) that needs to be found and eliminated.
Why should you not skip vacuuming?
The moisture remaining in the system will freeze in the capillary tube at the first start, forming an ice plug. This will lead to re-clogging after a few hours or days of operation of the refrigerator.
Filling with refrigerant and checking operation
After the system has been evacuated and checked for leaks, refrigerant is charged. For refrigerators Indesit most often used R600a (isobutane) or R134a. It is better to refuel on a scale, strictly following the number of grams indicated on the compressor nameplate or the inner wall of the refrigerator compartment. Overfilling or underfilling is equally harmful to the system.
If there are no accurate scales, you can use the current and temperature method, but it requires experience. When refilling R600a (which is explosive), ensure the area is well ventilated and eliminate any sources of sparking. Freon is supplied in the liquid phase (the cylinder is turned over) in small portions with pauses for the compressor to operate so that the oil does not foam and water hammer does not occur.
- ❄️ Connect the cylinder with freon to the service fitting through the pressure gauge station.
- ⚖️ Open the valve and release the gas, controlling the weight of the cylinder.
- 🔌 Turn on the refrigerator and control the pressure on the pressure gauge and the current on the ammeter.
- 🌡️ Bring the amount of refrigerant to normal until the tube at the outlet of the evaporator becomes uniformly cold.
After filling it is necessary to solder the filling tube. This must be done quickly, cutting the tube with a clamp while the compressor is running in order to create a slight excess pressure and immediately seal the end. This will prevent air from being sucked into the system.
Possible errors and precautions
Repairing a refrigeration circuit is full of nuances, and even experienced craftsmen make mistakes. One of the most common is overheating of the compressor or pipes during soldering. Copper has high thermal conductivity, and if you heat the soldering area for a long time, the heat will travel far, damaging the insulation of the motor windings or melting plastic parts nearby. Use heat sink clips or wet rags to protect adjacent elements.
Another common mistake is using the wrong oil. Regular mineral oil cannot be poured into systems with R134a and R600a freon, since it does not mix with these refrigerants and does not return to the compressor, causing its rapid wear. For such systems, synthetic oils (POE) are used, which are hygroscopic and require fast operation.
⚠️ Attention: If you are not confident in your abilities or do not have experience working with high pressure and fire, it is better to contact a service center. Incorrect soldering or charging can lead to failure of the refrigerator or a fire hazard.
It is also worth remembering the specifics of the R600a refrigerant. It is heavier than air and spreads along the floor. If a large concentration is leaked, it can cause suffocation in an unventilated area, and its spark leads to an explosion. Therefore, any work to depressurize a system with R600a should be carried out with the window open and electrical appliances turned off.
Frequently asked questions (FAQ)
Is it possible to clean a capillary tube without nitrogen using a compressor?
Theoretically, it is possible to blow out, but It is impossible to properly clean the system from moisture in this way. The compressor pumps air containing water vapor, which will freeze when the refrigerator is running and clog the capillary again. Nitrogen is a dry inert gas that pushes out moisture.
How much does it cost to replace a capillary tube during service?
The price consists of the cost of materials (copper tube, filter, freon, solder) and the complexity of the work. On average, repairs with replacement of the capillary and filter-drier can cost from 3,000 to 6,000 rubles, depending on the region and model of the refrigerator Indesit.
Why does the refrigerator freeze after cleaning, but does not turn off?
Most likely, the refrigerant dosage is incorrect. If there is little freon, there is not enough cooling capacity. If there is a lot, liquid freon enters the compressor, or heat exchange is disrupted. Also, the reason may be in the thermostat or temperature sensor.
Is it necessary to flush the system with alcohol before assembly?
Rinsing with special solvents (for example, isopropyl alcohol or freon R141b) is allowed only in extreme cases of severe contamination. However, after flushing, the system must be vacuumed for a very long time and thoroughly to remove any residual solvent, otherwise it will destroy the motor insulation.