A sudden cessation of cold in the chamber, a strange hum or complete silence instead of the usual hum - all these are sure signs that the heart of your refrigerator is out of order. Compressor It is the most complex and expensive component in the cooling system, and its breakdown often leaves the owner with a choice: call a specialist or try to cope on your own. For brand equipment Biryusa, which is famous for its maintainability and simplicity of design, the second option is quite realistic for a person with “straight” hands and a basic set of tools.
Before proceeding with dismantling, it is necessary to clearly diagnose the problem, as symptoms can be deceiving. Sometimes the lack of cold is caused by a refrigerant leak or a clogged capillary, and not by a burnt-out motor. However, if you are confident in the diagnosis and are determined to do it yourself, this article will become your detailed guide. We will analyze each stage, from preparing the tool to the final check of the system's tightness. replacing the unit yourself, this article will become your detailed guide. We will analyze each stage, from preparing the tool to the final check of the system’s tightness.
It is important to understand that working with refrigeration equipment requires not only mechanical skills, but also compliance with safety precautions. Electricity and compressed gas are dangerous neighbors, so precautions cannot be ignored. During your work, you will have to deal with soldering copper tubes and vacuuming the circuit, which requires care and precision. Replacing a compressor without subsequent evacuation of the system will lead to rapid failure of the new unit due to moisture and air inside the circuit.
Diagnostics of the malfunction and selection of a new unit
First The step should always be a thorough check. If the refrigerator Biryusa turns on, hums for a few seconds and turns off with a characteristic click, most likely the thermal protection relay has tripped. This may indicate an interturn short circuit in the motor windings or jamming of the piston group. You can check the integrity of the windings with a multimeter: the resistance between the starting and operating windings, as well as between each of them and the housing, must be within certain limits.
When choosing a new compressor, it is critical to consider not only the dimensions, but also the technical characteristics. Units may differ in power, type of refrigerant (R134a or R600a) and method of mounting the feet. For refrigerators Biryusa marking motors NKS-105, FKK-1050 or their modern analogues are often used. An error in the choice can lead to the fact that the new engine will operate in overload mode or simply will not fit into its standard positions.
It is also worth paying attention to the condition of the capacitor and start-up relay. If the system was contaminated with combustion products from the old engine, simply replacing the compressor will not have a long-term effect. In such cases, flushing the circuit with nitrogen is required, which is extremely difficult to do at home. Therefore, if after opening you see black tarry deposits inside the tubes, it is possible that repairs will become economically unfeasible.
Necessary tools and workplace preparation
High-quality repairs are impossible without proper equipment. You will need not only a standard set of screwdrivers and wrenches, but also specific equipment for working with refrigeration systems. The main tool will be a gas torch (propane-oxygen or propane-butane with oxygen enricher) for soldering copper connections. The use of tin or soft solders in high-temperature areas is unacceptable.
In addition, for proper filling and evacuation, a vacuum pump and a pressure gauge station (manifold) are required. Without creating a deep vacuum, moisture will remain in the system, which, when frozen, will turn into an ice plug in the capillary tube, blocking the circulation of freon. Also stock up on solder (usually a copper-phosphorus rod BCuP or silver solder) and flux, if required by the type of connection.
☑️ Tools for replacing the compressor
Preparing a workplace is not just clearing away debris. You will need good lighting and ventilation, since during soldering and possible bleeding of residual freon, the air should not stagnate. Provide free access to the rear wall of the refrigerator from all sides. Prepare a container in advance to collect oil that may spill out of the old compressor or tubes when they are depressurized.
⚠️ Attention: Freon is heavier than air and displaces oxygen. Work on bleeding the refrigerant and soldering should be carried out in a well-ventilated room or outdoors, away from open flames, except for the burner itself.
Removing the old compressor and preparing the system
The process begins with completely turning off the refrigerator Biryusa from the power supply. Let the unit sit for several hours to allow the oil to drain into the compressor crankcase. Then remove the rear panel covering the engine compartment. Before starting soldering work, it is necessary to bleed off any remaining refrigerant. To do this, saw off the thickest copper tube (discharge) in a place remote from the compressor and let the gas escape.
After removing the gas, you can begin to disconnect the electrical contacts and tubes. Carefully unsolder the suction and discharge tubes. Be careful not to damage the capacitor and other components located nearby. When heating copper connections, try not to overheat the adjacent areas so as not to melt the insulation of the wires or plastic structural elements.
Where to put the old oil?
Old oil from the compressor and system contains oxidation products and acidic impurities. It should not be poured down the drain or onto the ground. Collect the liquid in a sealed container and take it to a waste oil products collection point.
Unscrew the mounting bolts holding the compressor to the frame. Some models Biryusa may use rubber damper pads, which also need to be removed and moved to a new unit. Check the condition of the vibration isolators: if they are dry or cracked, they must be replaced, otherwise the new compressor will operate with increased noise.
Installing a new compressor and soldering connections
Install the new compressor in its original place, making sure that the transport The plugs on the pipes were removed immediately before soldering. Copper tubes should fit into the pipes with slight interference, but without distortion. Before soldering, clean the joints to a shine using fine sandpaper or a special brush. A clean surface is the key to high-quality sealing of the seam.
The soldering process requires skill. The burner flame is directed at the joint, heating both parts evenly. Solder should melt from the heat of the metal, not from direct contact with fire. When the temperature is sufficient, the solder will flow into the gap between the tube and the nozzle due to capillary effect. It is important not to overexpose the torch so as not to burn the copper and damage the internal insulation of the tubes.
| Connection type | Soldering temperature (approximately) | Solder type | Features |
|---|---|---|---|
| Copper-Copper | 700-800°C | Copper-phosphorus | Flux is not required, self-fluxing solder |
| Copper-Brass/Steel | 800-900°C | Silver or with flux | The mandatory use of flux is required |
| Steel-Steel | 900°C+ | Special refractory | The most complex unit, requires experience |
After soldering, allow the connections to cool naturally way. Do not try to speed up the process with water or compressed air, as sudden temperature changes can cause microcracks in the seam. Visually inspect the seams: they should be smooth, without sagging or cavities. If you notice defects, the soldering procedure will have to be repeated.
Evacuation of the system and charging with refrigerant
This is the most critical stage on which the service life of the new compressor depends. Connect the hose from the vacuum pump to the service connection (usually it is located on the discharge tube or specially routed). Turn on the pump and monitor the pressure gauge. The arrow should go into the “green zone” (vacuum pressure). Evacuation time depends on the power of the pump, but is usually at least 30-40 minutes.
Evacuation is necessary to remove air and, more importantly, water vapor from the system. Water in the refrigerant circulation circuit is unacceptable: when passing through the capillary tube, it freezes, forming an ice plug that blocks the freon flow. In addition, moisture reacts with oil and refrigerant, forming aggressive acids that corrode the motor windings from the inside.
After creating a vacuum, close the valve on the manifold and turn off the pump. If the pressure gauge needle remains in place for 15-20 minutes, then the system is sealed. Now you can start refueling. Open the valve on the freon cylinder and fill the system until the pressure specified in the technical documentation for your model is reached Biryusa. This is usually done with the compressor turned off.
Checking operation and tightness
After refueling, turn on the refrigerator. During the first minutes of operation, listen carefully to the sounds coming from the compressor. They should be smooth, without metallic clanging or excessive vibration. Check the heating of the condenser (grid at the back): it should warm up evenly, starting from the point where it leaves the compressor.
For a final check of tightness, use a soap solution. Apply it with a sponge or brush to all soldered areas and joints. The appearance of bubbles will indicate a leak. If a leak is found, the system will have to be evacuated again after the defect is eliminated. Also check the temperature in the evaporator (inside the chamber) after 30-40 minutes of operation - it should begin to drop steadily.
⚠️ Attention: If after starting the compressor runs for more than 10 minutes, but the condenser remains cold and the evaporator does not cool, an “air lock” may have formed in the system or the capillary tube has become clogged.
Make sure that the current consumption corresponds to the passport data. This can be done using a clamp meter, covering one of the compressor power wires. Excess current indicates overload, insufficient current indicates underload or problems with the valves. Normal operation is accompanied by cyclic turning on and off of the unit upon reaching the set temperature.
Frequently asked questions (FAQ)
Is it possible to replace an R134a compressor with an analogue from R600a?
No, this is strictly prohibited. Refrigerants R134a and R600a have different chemical properties, operating pressures and require different types of compressor oil. Mixing or replacing without a complete redesign of the system (replacing the condenser, evaporator, filter-drier) will lead to an explosive situation or equipment failure.
Is it necessary to change the filter-drier when replacing the compressor?
Yes, definitely. The filter drier is a disposable element. When the circuit is opened, it instantly absorbs moisture from the air and loses its properties. Installing an old filter will negate all evacuation efforts and lead to the formation of an ice plug.
Why does the new compressor get very hot?
In the first hours of operation, strong heating of the compressor housing (up to 70-90°C) may be the norm, especially if the system has not yet reached operating mode. However, if only one side is heated or the temperature is critical, check that the start relay is connected correctly, that there is an air lock in the system, or that the power of the new unit meets the requirements of the refrigerator.
How long does it take for the system to cool down after soldering?
You should not rush. Copper cools quickly, but to ensure the safety of the seam, it is better to wait 5-10 minutes before starting vacuuming. Rapid cooling with water is prohibited, as this creates thermal stress in the metal.