How to check the motor on the Atlant refrigerator: complete diagnostics of the compressor

When the refrigerator stops cooling or works intermittently, the first thing owners suspect is a freon leak or a thermostat failure. However, often the root of the problem lies in the very heart of the unit - compressorwhich in everyday life is called a motor. In refrigerators of the brand Atlant, popular in the post-Soviet space, this unit is reliable, but it is not immune to winding burnout or mechanical jamming. You can understand what exactly has gone wrong by carrying out competent diagnostics, without immediately resorting to calling a technician.

Before grabbing the tools, you should listen carefully to the operation of the equipment. Humming, clicking or complete silence when connected to the network can tell a lot about the condition electric motor. If you hear a characteristic hum that ends abruptly with a click of the relay, this is a sure sign that the engine is trying to start, but cannot. In such a situation, checking the electrical parameters becomes the only way to determine the future fate of the unit: repair or replacement.

It is important to understand that motor diagnostics is not only about electrics. The mechanical condition of the piston group also plays a critical role. Belarusian refrigerators they are often equipped with compressors of their own production or analogues from Danfoss, which have their own design features. Misinterpretation of symptoms can lead to the purchase of unnecessary parts. Therefore, we will analyze all stages of the test, from visual inspection to precise measurements with a tester.

⚠️ Attention: Before starting any work on diagnosing the motor, be sure to disconnect the refrigerator from the electrical network. Working with electrical appliances under voltage is deadly to life.

Primary diagnostics and visual inspection

The check should always begin with an external inspection and analysis of the behavior of the equipment. If the refrigerator Atlant hums, but does not cool, or the motor turns on for a few seconds and turns off, this is already half the diagnosis. Visually assess the condition of the rear of the unit where the compressor unit is located. The presence of traces of oil, soot or melted wiring may indicate that insulation breakdown has already occurred.

Pay attention to the temperature conditions of the compressor housing. If the motor is so hot that you can't touch it, or if it remains completely cold after an hour of operation, these are warning signs. In the first case, it is possible turn-to-turn short circuit, in the second - an open circuit or a malfunction of the starting relay. The refrigerator should operate cyclically, and the heating of the motor should be uniform and moderate.

• 🔍 Inspect the wires going to the motor for melted insulation or oxidation of contacts.
• 👂 Listen: a steady hum replaced by silence and a click? This is the work of a thermal protection relay.
• 🌡️ Touch the compressor housing (carefully!): excessive heating indicates an overload of the windings.

Often owners are faced with a situation where, after a power surge, the refrigerator stops starting. In this case, a visual inspection may not reveal anything, but a burning smell from the rear grille will be eloquent evidence of the problem. If there are no external signs, we proceed to a deeper analysis using measuring instruments.

Necessary tools for checking the motor

For high-quality diagnostics, you will need a minimum set of tools, which is found in most home craftsmen. The main device will be multimeter (tester), capable of measuring resistance in Ohms and current in Amperes. Without this device, it is almost impossible to check the integrity of the windings and the absence of breakdown on the housing. A screwdriver is also useful for removing the compressor protective casing.

If you plan to check the starting current, which is the most accurate diagnostic method, you will need a current clamp. However, for a basic check of winding resistance, a regular digital multimeter is sufficient. Make sure that the device is working properly and that its probes have intact insulation. Refrigerators Atlant with inverter compressors may require more complex equipment, but classic models are tested as standard.

Don't forget about safety. Rubber gloves and a dielectric mat under your feet will not be superfluous, especially if the test is carried out in a room with a wet floor. Preparing the workplace is the key to ensuring that you do not damage fragile wiring elements or tubes when dismantling the protective cover.

Checking the resistance of the windings with a multimeter

The most reliable way to determine the condition of the electric motor is to measure the resistance of the windings. To do this, you need to remove the protective plastic casing from the compressor and disconnect the start relay. On the contact group you will see three pins: two upper and one lower (or arranged in a triangle). Usually they are marked, but if there is no marking, you will have to use the method of elimination.

Switch the multimeter to resistance measurement mode (2 kOhm). First check the resistance between each terminal and the compressor housing (where there is no paint). If the device shows one (infinity), the insulation is intact. If the arrow goes to zero or shows a specific low value, it means that something has happened breakdown to the housing. Such a motor cannot be operated, it is dangerous to life.

Next, we measure the resistance between the contacts themselves. Single-phase motors, which are found in most refrigerators Atlant, have a starting and operating winding. The resistance of the starting winding is always higher than that of the working winding. The third measurement is between the two remaining contacts (total resistance). These data need to be compared with the table values for your type of compressor.

⚠️ Attention: If the resistance of the starting winding is significantly higher than normal or equal to infinity, the thermistor built into the winding may have burned out (in modern models). This requires replacing the entire compressor.

Trembling readings may indicate poor contact of the probes or oxidation of the contacts on the motor itself. Clean the contacts with fine sandpaper before re-measuring.

What to do if the values ​​are close to normal, but the motor does not work?

If the winding resistance is normal, but the compressor hums and does not start, the problem may be a mechanical jamming of the piston group or a faulty start relay. Sometimes “wedging” by applying increased voltage helps, but this is a job for professionals.

Diagnostics of the starting relay and motor protection

Often the motor itself is working, and the problem lies in the starting relay, which supplies an impulse to the starting winding. Refrigerators Atlant use different types of relays: posistor and induction. If the relay is faulty, the engine will hum but will not start, which can quickly lead to its combustion due to overheating.

Checking the relay begins with a visual inspection. Shake it: if you hear the sound of broken parts inside, the relay is definitely faulty. To electrically test the posistor (the black tablet inside the relay), test it with a multimeter. When cold it should have low resistance, and when heated it should go to infinity. Induction relays are checked for the integrity of the coil.

• 🔌 Remove the relay from the compressor connector, having previously photographed the position of the contacts.
• 📉 Measure the resistance of the induction relay coil: it should be within the normal range (usually tens of ohms).
• 🔥 Check posistor: when cold, the resistance is about 10-30 Ohms, when heated with a hairdryer it should increase.

Do not forget that the thermal protection relay can also cause the motor to stop. It opens the circuit when overheated. If the bimetallic strip inside does not return to its original position, the motor will not turn on. Check the contacts of the thermal relay for carbon deposits and oxidation.

Checking starting current and mechanics

If the electrical parameters are normal, but the motor is behaving strangely, you need to check the starting current. To do this, a multimeter with the function of measuring alternating current (or current clamp) is connected to the compressor power supply circuit. At the moment of startup, the current briefly increases by 3-5 times compared to the operating current. If there is no jump, the starting winding does not work or the relay does not give an impulse.

Mechanical testing is more complex and requires experience. If the compressor hums, the current consumption is high, but the shaft does not turn, the piston group may be jammed. Sometimes a short-term supply of voltage directly to the working winding (bypassing the relay) using an isolation transformer helps, but the risk of completely killing the motor is very high.

Listen to the sound of operation. Metallic knocking, clanging or strong vibration indicate destruction of internal elements: valves, pistons or engine suspension. In such cases compressor repair it is not economically feasible; a complete replacement of the unit is required. The sealed housing is not intended for opening at home.

Typical malfunctions of Atlant compressors

Refrigerators Atlant have their own characteristic “diseases”. For example, compressors of the SKN series (our own production) are prone to burnout of the starting winding due to frequent power surges. Models with foreign compressors (Danfoss, Secop) more often suffer from loss of performance due to valve wear, although the electrical part remains intact.

Another common problem is moisture getting into the system. If there is water in the circuit, it freezes in the capillary tube, creating a plug. The discharge pressure increases, the motor is overloaded and may burn out. Checking the motor in this case will show normal resistance, but the operating current will be increased, and the body temperature will be critical.

You should not ignore the condition of the capacitor (if it is in the circuit). Swelling or leaking electrolyte from the capacitor can disrupt the phase of current needed to start the engine. Replacing this element costs a penny, but can revive the refrigerator.

When a compressor replacement is needed

Replacement of the motor is necessary if a breakdown in the housing, an interturn short circuit or mechanical jamming is detected. They also change the compressor when there is a loss of performance, when freon circulates, but there is not enough pressure for normal cooling. In the case of refrigerators Atlant, it is often cheaper and more reliable to replace the entire unit if it is more than 10-12 years old.

The replacement process requires not only installing a new motor, but also completely recharging the system with refrigerant, replacing the filter-drier and evacuating the circuit. Without special equipment (vacuum pump, pressure gauge station, scales) it is impossible to perform this work efficiently. Therefore, motor diagnostics is only the first stage, followed by an assessment of the economic feasibility of repairs.

⚠️ Attention: Replacing the compressor yourself using a non-vacuum method ("squeezing out" freon) leads to rapid failure of the new motor. Professional sealing and refueling are required.

Frequently asked questions (FAQ)

Is it possible to repair a burnt-out compressor of an Atlant refrigerator?

At home, it is impossible to rewind the windings of a hermetic compressor. Requires special equipment for opening, balancing and sealing. It is easier and more reliable to buy a new or used compressor assembly.

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

This may indicate a loss of compression (wear of valves), a blockage in the system or a freon leak. The motor idles, overheats, but does not create the necessary pressure for the circulation of the refrigerant.

How to distinguish a motor malfunction from a thermostat breakdown?

If the motor does not turn on at all and does not make sounds, close the thermostat contacts. If the motor starts working, the problem is in the thermostat. If the motor hums, clicks and turns off, the problem is in the motor, relay or starting system.

How much does a new compressor cost for Atlanta?

The price of a new original compressor varies from 4,000 to 8,000 rubles depending on the model and power. To this amount you need to add the cost of replacement and refueling, which often makes the repair comparable to buying a new budget refrigerator.