When extraneous noise occurs, lack of cold or constant clicks in the rear of the unit, owners often wonder what exactly their engine looks like refrigerator. The compressor is the heart of the system, and understanding its visual design helps not only in diagnosis, but also in the selection of replacement parts. Refrigerators Atlant use predominantly hermetic piston compressors, which have a characteristic appearance that differs little from analogues from other manufacturers, but has its own specific markers.
Visually compressor is a massive metal cylinder or barrel, painted black. It is located in the lower rear part of the refrigerator, fixed to the frame using special shock-absorbing bushings. It is this unit that is responsible for compressing the refrigerant and circulating it through the pipe system. If you see that black cylinder with copper tubing extending from it, you are looking at the main motor of your refrigeration unit.
It is important to understand that the appearance of the part may vary depending on the year of the model and the type of refrigerant used. Older models may have a more elongated body shape, while modern versions are often more compact and rounded. A critical difference is the type of refrigerant: for R600a (isobutane) compressors often have a smaller working volume chambers, which may not be visually obvious, but is reflected in the marking. Differences in body size and shape directly affect replacement compatibility, so visual similarity is not enough.
Main structural elements of the compressor
Looking at the motor-compressor Atlant close-up, we can identify several key zones, each of which performs a strictly defined function. The upper part of the case is usually smooth, but there is always a sticker or embossed marking with technical data on it. This is where the power, freon type, voltage and production date are indicated. Without reading this data, it is impossible to accurately identify the device model.
At the bottom of the case, where the metal often has a darker or matte tint due to factory processing, there are three contact pins. They are hidden under a plastic casing that protects the electrical part from moisture and dust. These contacts are the connection point for the start and run relays. Incorrect connection or oxidation in this area is a common cause of equipment failure.
Copper tubes come out from the side or behind the cylinder. Usually there are two of them: one suction (thicker) and one discharge (thinner). In some modifications, there may be a third tube - a technological one, sealed at the factory, but in modern models Atlant it is often absent, which complicates refilling with freon without cutting the system. Tightness these connections are the key to the long life of the refrigerator.
For a better understanding of the arrangement of elements, consider them in a comparative table, which will help you navigate during a visual inspection:
| Element | Location | Appearance | Function |
|---|---|---|---|
| House | Central part | Black cylinder | Stores oil and mechanics |
| Contact group | Bottom/Side | Three pins in the casing | Electricity supply |
| Suction tube | Side/Back | Thick copper pipe | Gas intake from the evaporator |
| Discharge tube | Side/Back | Thin copper pipe | Gas supply to the condenser |
Differences between models of Atlant compressors
The manufacturer Atlant over the years of production used different types of engines, and they differ significantly in appearance. The main division occurs according to the type of refrigerant: R134a and R600a. Compressors for freon R134a usually have a more classic, slightly elongated “barrel” shape. Their body often has characteristic stiffening ribs or stamping on the sides.
Models working on R600aoften look more “potbellied” or, conversely, more compact and squat. This is due to the fact that isobutane requires less substance to operate, and the motor design is optimized for other pressure parameters. It is difficult to visually distinguish them only by the shape of the body, but an experienced technician will pay attention to the diameter of the suction tube - in the R600a it is often thinner.
⚠️ Attention: Do not try to replace a compressor designed for one type of freon with an analogue for another type, even if they fit in size. Different oils and different operating pressures will lead to rapid failure of the entire system.
It is also worth noting the difference in the manufacturers of the motors themselves, which are installed at the factory. Atlant. These can be original Belarusian units, as well as licensed copies or components from Danfoss (now Secop) or Embraco. Original Belarusian motors often have simpler stamping and a specific logo on the nameplate, while European analogues are distinguished by more accurate welding of seams and a different form of protective cap for contacts.
Marking and identification of the device
The most reliable way to understand what exactly is installed in your refrigerator is - read the label. It is applied to a metal tag glued to the top of the case, or pressed directly onto the metal. All necessary information is encrypted in the model code. For example, the marking may begin with letters indicating the type of refrigerant, or contain numbers indicating the volume of the compression chamber.
Pay attention to the electrical parameters. The nameplate must indicate voltage (220-230 V) and frequency (50 Hz). There is also a current value, usually in the range from 1.0 to 1.5 Ampere for household models. These numbers should match the requirements of your starting relay. If you are planning a replacement, the search for a new motor should be carried out precisely by this code, and not by external similarity.
Often you can find color markings on the housing tubes or the ports themselves, although this is less common. More informative is the color of the plastic casing of the contact group. In older models, it could be white or gray; in new ones, black or dark blue plastic, resistant to high temperatures, is more common.
To correctly decipher the code, you often need to refer to the technical documentation, but there are general rules. The first two numbers often indicate the series, and the letter at the end may indicate energy efficiency or the type of oil. POE (polyester) oil is used with R134a and R600a freon, it is hygroscopic and requires special care during installation. Mineral oil, used in ancient models with R12, is now almost never found.
Symptoms of malfunction and visual diagnostics
Understanding what a working engine looks like helps to notice signs of its death in time. A working compressor operates with a smooth, low hum. The vibration of the body should be uniform. If you see that the motor housing is covered with a layer of oil or drops of liquid appear on it, this is an alarming signal. The oil should not leave the sealed circuit.
One of the most obvious visual signs of a problem is swelling or deformation of the housing. Although the metal of the housing is very strong, if there is an internal short circuit or water hammer, the geometry may be disrupted. It is also worth inspecting the exit points of the copper pipes. If the copper is blackened or has green oxidation marks, there may be a leak or overheating in this area.
Pay attention to the condition of the thermal insulator, if present on the suction tube. This is a black foam or rubber cover. If it has slipped, melted or is missing, the compressor may overheat because it is receiving already heated gas rather than cold gas.
⚠️ Attention: If you notice traces of soot on the motor wall or the smell of galling wiring, immediately unplug the refrigerator. This may indicate an interturn short circuit of the windings, which is a fire hazard.
Replacement process and technical nuances
Replacing a motor-compressor is a complex technical process that requires special equipment. Visually, the procedure begins with dismantling the protective cover and disconnecting the unit from the network. Then the master cuts off the copper tubes, desoldering them from the system. It is important not to damage the capillary tube, which is very thin and fragile.
The new motor is installed in the same seats. However, it often happens that the distances between the mounting feet differ from one manufacturer to another. In such cases, a universal mounting frame or adapter bushings are used. Vibration isolation Here plays a key role: if you fix the motor rigidly, the refrigerator will rumble during operation.
After physical installation, the connections are soldered. This is where it is critical to use the correct solder and flux to ensure a seal. The system is then evacuated to remove moisture and air before refrigerant is charged. The amount of gas must be strictly according to the grams indicated on the nameplate.
☑️ Check before starting
The final stage is the installation of a protective casing and a starting relay. The relay is put on the contacts until it clicks and is fixed with a bracket or spring. Incorrect installation of the relay (upside down) will result in the motor not starting or burning out after a few seconds. The orientation of the relay is always indicated by an arrow or an inscription TOP.
Frequent questions and misconceptions
There are many myths around the design of refrigeration motors. For example, many people believe that if the engine is hot, then it is broken. In fact, the temperature of the housing of a running compressor can reach 70-90 degrees Celsius, and this is normal. It heats up due to gas compression and friction of mechanical parts. You should sound the alarm if it is red-hot or smoke is coming from it.
Another misconception concerns the “repair” of the motor. The sealed case Atlant is not intended to be opened. Attempts to disassemble it, replace valves or bearings in a garage are doomed to failure. Once opened, the geometry is broken, and it is impossible to reassemble it with factory tightness. Therefore diagnostics usually comes down to a decision: to change or not to change.
Why can’t you use a compressor from an air conditioner?
Air conditioner compressors operate on a different type of oil and often with higher pressures. In addition, their electrical characteristics and starting currents may not coincide with the refrigerator relay, which will lead to breakdown.
Users are also interested in why motors Atlant are sometimes called “rumble”. This is a design feature of the piston group of older series. Modern models are much quieter, but completely silent piston compressors do not exist. If the noise has become sharply louder or has changed in tone, this is a reason to call a technician.
Is it possible to determine the type of freon only by appearance of the motor?
It is impossible to accurately determine the type of freon only by the shape of the housing. R134a and R600a may have similar dimensions. The only reliable way is to read the marking on the nameplate, which indicates the type of refrigerant (for example, R600a) or the type of oil (POE for modern freons).
Why is there a third sealed tube on the motor?
The process tube was used on older models to charge and evacuate the system. In modern refrigerators Atlant it is often abandoned in favor of charging through a suction tube, which requires more complex equipment, but simplifies the design of the compressor itself.
What does a humming sound mean without starting the engine?
If you hear a humming sound, but the compressor does not start (or starts for a couple of seconds and clicks), this most often indicates a faulty start relay or a jammed piston group. Visually, the relay may look intact, but the bimetallic element inside could have burned out.