How to check the engine of an Atlant refrigerator: complete diagnostics

A sudden stop of the refrigerator Atlant is always stressful, because food supplies are at risk. Most often, owners are faced with a situation where the unit turns on, hums for a couple of seconds and turns off, or is silent, although the light in the chamber is on. In 80% of such cases, the problem lies in the operation of the compressor or its startup circuits. Understanding how to check the enginewill allow you to save a significant amount on calling a technician or immediately determine that you cannot do without replacing the unit.

The compressor is the heart of the refrigeration system, creating the necessary pressure for the circulation of the refrigerant. Models Atlant most often have piston engines, which are reliable, but are subject to wear over time. Before starting any work, you must clearly understand: you will be dealing with high voltage of 220 volts. Any carelessness can lead to electric shock or permanent failure of the equipment. If you are not confident in your skills in handling a multimeter, it is better to stop at this stage.

This article will help you carry out initial diagnostics using a minimal set of tools. We will look at methods for checking the integrity of the windings, assessing the condition of the starting relay and analyzing the mechanical part of the motor. Competent diagnostics takes no more than 30 minutes, but gives a complete understanding of the condition of your refrigerator. Do not ignore signs of malfunction, as a running but not cooling compressor can consume a huge amount of electricity.

Primary visual diagnostics and preparation

Before taking up measuring instruments, it is necessary to conduct a thorough external inspection. Often the cause of the breakdown is visible to the naked eye. Unplug the refrigerator Atlant from the electrical outlet and move it away from the wall, allowing access to the rear panel. You will need to remove the compressor guard, which is usually secured with clips or screws. Carefully inspect the wires going to the motor: there should be no traces of melting, carbon deposits or mechanical damage to the insulation.

Pay attention to the motor housing itself. If you see oily streaks at the bottom of the compressor or on the connecting pipes, this is an alarming sign. The seal of the housing is broken, and, most likely, oil leaked through the seals or cracks. In this case, further diagnostics of the electrical part becomes meaningless - the unit requires replacement. Also check the condition of the condenser grille (radiator) at the rear: if it is severely deformed or clogged with dust, this could lead to overheating and thermal shock of the engine.

⚠️ Attention: If you find that the tubes coming from the compressor are pinched, flattened or have signs of corrosion with holes, do not under any circumstances try to start the engine. This can lead to depressurization of the system and the release of freon, which will require expensive repairs with refilling.

Inspect the start-protection relay mounted on the side rod of the compressor. The plastic case should not have cracks, and there should be no burning smell inside. Often it is the Relay that is the culprit of the problem, while the engine itself remains operational. A visual inspection allows you to eliminate 20% of obvious problems associated with external factors and move on to a deeper check of the electrical parameters.

Necessary tools for testing

For high-quality diagnostics of the refrigerator engine Atlant you will need a specific but accessible set of tools. Without them, the check will be incomplete and may give false results. The main device will be a multimeter (tester) capable of measuring resistance in the range from 0 to 2000 Ohms and checking the integrity of the circuit (continuity). It is desirable that the device has the function of measuring the inrush current, but for a basic check, an ordinary household tester is sufficient.

In addition to the multimeter, prepare the following tool:

• 🔧 A set of screwdrivers (phillips and flat) for removing the casing and terminals.
• 🧤 Dielectric gloves for protection against residual voltage.
• 🔦 A powerful flashlight for illuminating hard-to-reach places behind the unit.
• 🧹 A soft brush for cleaning contacts from dust and oxides.
• 📏 Pliers with insulated handles for careful removal of the terminals.

It is important that the multimeter probes are in good working order and that the battery in the device is not discharged, otherwise the resistance readings will be distorted. Before starting measurements, check the operation of the tester by connecting the probes to each other: the device should show zero or a value close to it. If you plan to check the starting current, you may need current clamps, but they are not required for initial diagnostics of the windings.

Carry out all work only with the refrigerator completely disconnected from the network. Even after unplugging, capacitors may retain charge. Let the equipment sit for 10-15 minutes before disassembling. This simple safety rule will protect you from unpleasant surprises in the form of a short circuit or electric shock when touching metal parts.

Checking the integrity of the motor windings

The most important diagnostic stage is checking the electrical resistance of the stator windings. Compressors Atlant, like most modern refrigerators, are equipped with electric motors with starting and operating windings. To access the contacts, you must carefully remove the start-up relay. It is simply put on three terminals located at the bottom or side of the compressor in the form of a triangle.

On the block you will see three contacts. Usually they are marked, but if there is no marking, remember their location: the two upper contacts are windings, and the lower one (or the one that is separate) is common. The layout may differ on some models. You need to call the resistance between each pair of contacts. Normal resistance values for a working compressor vary within the following limits:

If the multimeter shows one (infinity) between the contacts of the windings, this means open circuit. In this case, no current flows and the motor will not start. Repair at home is impossible; the compressor must be rewinded or replaced. If the device shows zero or a value very close to zero, this indicates interturn short circuit. Such a motor will hum, get warm and knock out the circuit breaker in the apartment.

Pay special attention to checking for breakdown of the housing. Place one multimeter probe on any of the three contacts, and the other on a cleaned area on the metal compressor housing (where there is no paint). The device should show infinity. If there is any resistance or a squeaking sound is heard, it means that the insulation of the windings is broken and the motor is “breaking through” to the housing. Operating such a unit is deadly.

Diagnostics of the starting relay and thermal protection

Often the engine itself Atlant is working, but cannot start due to a faulty starting relay. This small block is responsible for briefly supplying voltage to the starting winding. Inside the relay there is a posistor (thermistor), which, when heated, sharply increases its resistance, opening the starting circuit. If the posistor is destroyed, the engine will only hum without starting.

To check the relay, you need to remove it and carefully open the case (usually it is held on by latches). Visually inspect the insides: if you see black carbon deposits, melted plastic, or smell a burning smell, the part is faulty. The posistor must be intact, without cracks. Check its resistance with a multimeter: when cold it should be small (several tens of Ohms), and when heated (you can warm it up with a hairdryer or lighter, being careful) it should go to infinity.

⚠️ Attention: Do not try to start the compressor directly, bypassing the relay, for more than 2-3 seconds. The starting winding is not designed for long-term operation and will burn out almost instantly, which will lead to the need to replace the entire expensive unit.

Also, a thermal protection relay is often present in the circuit. It opens the circuit when the compressor overheats. Check its contacts for short circuit: in a cold state they should ring (resistance is close to 0). If the circuit is open even when the engine is cold, the thermal relay must be replaced. Ignoring this element can lead to the new compressor burning out immediately after installation due to the lack of overload protection.

Why does the posistor burn out?

The posistor in the relay burns out most often due to frequent voltage drops in the network or attempts to start a “jammed” compressor. If you simply replace the relay and the cause was a power surge, history may repeat itself. It is recommended to install a voltage stabilizer to protect all household appliances.

Mechanical check and assessment of the condition of the compressor

If the electrical part is in order, it is worth assessing the mechanical condition of the motor. Jamming of the piston group is a common cause of failure of old refrigerators Atlant. This occurs due to oil production, moisture entering the system, or prolonged downtime. You can check this by trying to turn the motor shaft (although on hermetic compressors it is difficult to do this without disassembly) or indirectly - by the nature of the sound when trying to start.

If, when turned on, the refrigerator makes a loud, increasing hum, and after 5-10 seconds a click is heard and silence sets in - these are classic signs wedge or interturn closure. At this moment, the current in the circuit increases sharply, and thermal protection is triggered. Another sign of a mechanical problem may be a lack of vibration from the housing of the compressor running (or trying to run). A serviceable motor always vibrates.

For more accurate diagnostics of mechanics, professionals use a pressure gauge station, connecting to the service fitting. However, at home you can assess the pressure by hearing and tactilely (carefully!). If the compressor runs but does not create pressure (the tubes do not heat/cool according to the cycle), the connecting rod may have broken or the valves may have worn out. In this case, the motor hums smoothly, without turning off, but there is no cold.

Analysis of current consumption (for advanced)

The most accurate diagnostic method available to home craftsmen with the appropriate equipment is measuring the starting and operating current. To do this you will need current clamps. The normal operating current for compressors Atlant with a power of about 100-140 W is 0.5 - 0.8 Ampere. The starting current can briefly jump to 3-4 Amperes, but immediately fall.

If, during startup, the current instantly increases to 10-12 Amperes and knocks out the circuit breakers, this is a sure sign of a short circuit in the windings. If the current is low (0.2-0.3 A), but the compressor is humming, a mechanical wedge or loss of compression is likely. Measuring current allows you to differentiate an electrical fault from a mechanical one without opening the housing.

Be extremely careful when making these measurements. You will have to apply voltage to the bare relay contacts or use adapters. All connections must be reliably insulated, and hands must be protected with dielectric gloves. Do not take measurements alone; having an assistant who, if something happens, can turn off the switch will significantly increase safety.

Frequent errors in diagnostics

Beginners often make mistakes that lead to false conclusions. One of the most common is checking the resistance on dirty or oxidized contacts. Before measurements, be sure to clean the compressor leads and relay terminals with fine sandpaper or a knife to a metallic shine. Oxides can produce high resistance, simulating a break.

Another mistake is ignoring the condition of the wiring. Even if the compressor itself is working, a burnt wire in the area from the socket to the relay or a faulty plug will prevent the engine from starting. Always check the integrity of the chain along its entire length. Also, do not forget about the capacitor (if your relay model has one); its swelling or loss of capacity also prevents normal engine starting.

Remember that modern inverter compressors (found in new models Atlant) are diagnosed differently. They cannot simply be “clicked” by a relay or supplied with 220V directly. To check the inverter motor you need a special tester or control unit. An attempt to start an inverter compressor using conventional methods will lead to the control board burning out.

Is it possible to restore a jammed compressor?

There is a method of “wedging” by applying increased voltage (380V) for a short time, but at home this is extremely dangerous and rarely gives long-term results result. Most often, such a compressor works for several more months and finally fails. It is more economically feasible to replace the unit.

Why is the compressor hot, but the refrigerator does not freeze?

This indicates that the motor is running, but there is no freon circulation. Causes: refrigerant leak, capillary system blockage or broken valves inside the compressor. A call to a technician is required to find leaks and refill.

Is it worth replacing the compressor on an old Atlanta?

If the refrigerator is more than 10-12 years old, replacing the compressor may not be economically feasible, since the cost of work and a new unit can be up to 70% of the price of a new refrigerator. Also, the thermal insulation in the old housing may be worn out.

Which compressor is better to install instead of the standard one?

It is recommended to install original compressors Atlant or proven analogues (for example, Danfoss/Secop, Embraco) with similar performance characteristics (see markings on nameplate). It is important to observe the overall dimensions and type of refrigerant.