The sudden stop of operation of a household appliance often takes you by surprise, especially when there is perishable food stock inside. If you notice that refrigerator has stopped freezing, and strange clicks or complete silence are heard from the back of the case, most likely the compressor has failed. Independent replacement of this unit falls into the category of complex repairs, requiring not only technical knowledge, but also specific tools for working with refrigerants.
Before proceeding with dismantling, you need to make sure that the diagnosis is correct, since the symptoms of a non-working compressor can simulate a malfunction of the start relay or thermostat. It is important to understand that motor-compressor is the heart of the system, and its replacement entails a violation of the tightness of the circuit, which will require subsequent evacuation and filling. freon. Without special equipment, it is almost impossible to perform these steps efficiently.
In this article we will analyze in detail the algorithm of actions, the necessary tools and precautions that must be observed when replacing the engine. You will learn about the intricacies of selecting analogs for models Indesit, Atlant and other popular brands, and will also understand when it is really worth getting down to business yourself, and when it is better to call a professional technician with a license.
Diagnostics of a compressor malfunction
The first step should always be a thorough diagnosis, excluding simpler breakdowns. If refrigerator compartment it is not cooling, but the light is on inside and there are no errors on the control panel, listen to the sounds made by the unit. A dull hum that turns into a click and fades out often indicates that the motor is trying to start, but cannot turn the shaft or is lacking power due to electrical problems.
However, do not rush to buy a new unit until you check the starting relay and capacitor. These parts are inexpensive and often fail before the engine itself. To check the relay, you need to carefully remove it from the compressor contacts and shake it: if a ringing sound is heard inside, it means that the mechanical part is destroyed. Also test the motor windings with a multimeter - the resistance between the contacts should be within normal limits and not show an open or short circuit.
⚠️ Attention: If, when you try to start, the compressor hums and then the thermal protection is triggered, under no circumstances leave the device plugged in for a long time. This can lead to burnout of the windings and the final failure of the unit without the possibility of recovery.
If the electrical part is in good order, but there is no characteristic vibration hum and cooling, the problem lies in the mechanical part - jamming of the piston group or loss of compression. In such cases replacing the motor becomes the only viable option for restoring the functionality of the equipment. It is also important to check the integrity of the supply pipes: if you can hear gas escaping from them, it means that the seal has already been broken.
Necessary tools and materials
To successfully implement the engine replacement project, you will need a set of professional equipment that is rarely found in everyday life. The main tool will be burner (oxygen-propane or acetylene) for soldering copper tubes, since ordinary solder without strong heating will not ensure a tight connection under pressure. It is also necessary to have a pipe cutter to carefully separate the old compressor without damaging the rest of the system.
A critical step is working with the refrigerant, so you will need a pressure gauge station (manifold) and a vacuum pump. Without creating a deep vacuum, moisture and air will remain in the system, which will lead to the formation of acids and rapid failure of the new compressor. In addition, you need a cylinder with freon grade R600a or R134a, corresponding to the one indicated on the nameplate of your refrigerator.
Don't forget to prepare consumables and auxiliary tools:
- 🛠️ Copper tubes of different diameters for extending fittings (if the old ones are too short).
- 🔥 Flux and solder for soldering copper connections (phosphorus-containing solder for copper).
- 🧹 Nitrogen or dry air for purging the system (optional, but desirable).
- 🔧 A set of wrenches, screwdrivers and pliers for dismantling the housing.
☑️ Preparation for repair
It is worth noting that the use of unsuitable materials, for example, ordinary tin solder instead of refractory solder, can lead to depressurization of the circuit during operation. The pressure in the system can fluctuate, and a weak connection will simply burst. Therefore, approach your choice consumables with maximum responsibility.
Removing the old compressor
The process of removing a faulty unit begins with completely disconnecting the refrigerator from the power supply. It is necessary to remove the rear metal panel that blocks access to the engine compartment. In modern models, such as Samsung or LG, access may be limited by plastic casings that require careful handling so as not to break the latches.
After gaining access to the compressor, you need to bleed off the remaining refrigerant. If there is pressure in the system, you will hear a characteristic hissing sound when the process tube is punctured. Next, using a pipe cutter or wire cutters (for thin pipes), the suction and discharge pipes are cut. It is important to do this carefully so that metal shavings do not get inside the open tubes of the system, as this can clog capillary.
⚠️ Attention: When cutting the tubes, try not to damage the filter drier if you plan to reuse it (although replacing the filter is mandatory for any intervention in the circuit). Immediately process the sharp edges of copper pipes with a file.
The next step is to disconnect the electrical wires. Take a photo of the connection diagram or sketch it so that when installing a new motor you do not mix up the contacts. The compressor is attached to the refrigerator frame using four rubber shock absorbers or metal legs with bolts. Carefully remove the engine from the mounts, being careful not to drop it or damage the surrounding elements.
Preparation and installation of a new motor
The new one compressor must fully comply with the technical characteristics of the old one: power, type of coolant, type of oil and overall dimensions. Pay attention to the location of the fittings - they must match, otherwise you will have to bend the copper tubes, which is undesirable. Before installation, remove the transport plugs from the pipes of the new engine.
Install the motor in its original place and secure it with fasteners, not forgetting the vibration-isolating bushings. If the old bushings are dry, they must be replaced, otherwise vibration will be transmitted to the refrigerator body, creating a lot of noise. Connect the electrical part, following the previously made diagram or color coding of the wires.
Now you need to prepare the system for soldering. A new element is installed in place of the old filter-drier, since the filter that opened the circuit has already been saturated with moisture from the air and will not be able to perform its function. Soldering a new filter and connecting compressor tubes to the refrigerator circuit requires skill in working with an open flame.
Nuances of soldering copper tubes
When soldering, it is important not to overheat the tube, otherwise the solder will not flow inside, but will simply remain outside. The torch flame should be directed at the joint, not at the solder itself. Use flux for better flow, but remove any remaining flux after it cools to avoid corrosion.
It is critical when soldering to prevent air from entering the system. To do this, they often use nitrogen purging or, in extreme cases, their own refrigerant, creating a slight excess pressure. This prevents oxidation of copper from the inside, which can subsequently clog the system.
Evacuation and refrigerant charging
After checking the tightness of the connections (pressure testing with nitrogen), the evacuation stage begins. A vacuum pump is connected to the process pipe. The operating time of the pump depends on the volume of the system, but is usually at least 30-40 minutes. The goal is to remove all moisture and air, since the presence of air increases the condensation pressure and discharge temperature, which is detrimental to the compressor.
After reaching the required vacuum, the valves are closed and the filling process begins. Freon is charged strictly by weight, since the amount of refrigerant in modern refrigerators is very small (often 30-60 grams). Overfilling or underfilling will lead to incorrect operation: in the first case, electricity consumption and the load on the motor will increase, in the second, the refrigerator will stop freezing.
| Refrigerant type | Suction pressure (bar) | Discharge pressure (bar) | Features |
|---|---|---|---|