Did the refrigerator Samsung stop freezing or start working with an uncharacteristic hum? In most cases, users immediately fall for the most expensive unit - compressor, believing that its breakdown automatically means the purchase of new equipment. However, you should not rush to conclusions, since often the problem lies in cheaper elements of the circuit, such as a start relay or thermostat.
Before disassembling the unit, you need to clearly understand that diagnosis requires strict safety measures, since you will be dealing with electric current under voltage 220 volts. Incorrect actions can lead not only to the final failure of the electronics, but also to electric shock. In this article, we will analyze a step-by-step algorithm for checking the motor of a Samsung refrigerator so that you can accurately determine the cause of the silence or noise of the unit.
Modern models, such as the series Digital Inverter, are equipped with complex control electronics, and their testing differs from the diagnosis of classic single-phase motors. If your refrigerator hums but won't start, or starts and immediately stalls, these are classic symptoms of problems in the compressor circuit. Let's figure out how to distinguish a burnt out motor from a fault in the wiring or control unit.
Initial visual assessment and signs of malfunction
Any diagnostics begins with an external inspection and analysis of the sounds that the unit makes. Do not rush to open the back wall if the refrigerator has just stopped cooling. Listen carefully to the device for 10-15 minutes. If you hear a quiet hum, which ends abruptly with a click, and repeats cyclically, this indicates that the motor is trying to start, but cannot turn the shaft or gain speed.
Pay attention to the temperature of the compressor housing. If, while the refrigerator is running (or attempting to operate it), the metal barrel of the motor becomes hot to the point where it is impossible to touch it without being burned, this is an alarming signal. Normal operating temperature is about 50-60 degrees Celsius, but not more than 90. Overheating often indicates an interturn short circuit of the windings or jamming of the piston group.
⚠️ Attention: If you smell burnt wiring or see sparking in the motor-compressor area, immediately disconnect the refrigerator from the network. Further operation in this condition may lead to a fire.
It is also worth inspecting the condenser and evaporator tubes. If the compressor is running, but there is no cold, check if the tubes are pinched and if there are traces of oil at the connections. Oil on the pipes near the compressor is a sure sign of depressurization of the system, which is often confused with a breakdown of the motor itself. In this case, replacing the compressor will not solve the problem without evacuation and refilling with freon.
Necessary tools and preparation for diagnostics
To conduct a quality test, you will need a minimum set of tools that any home craftsman will have. The main device will be multimeter (tester), capable of measuring resistance in Ohms. Without this device, it is almost impossible to accurately diagnose the windings, since it is impossible to determine the integrity of the coil “by eye.”
In addition to the multimeter, prepare screwdrivers (Phillips and flathead) for removing the rear protective panel of the refrigerator Samsung. On some models, access to the compressor may be limited by plastic covers that require careful handling. It would also be a good idea to have pliers and electrical tape for temporary insulation of contacts.
☑️ Tools for testing
It is important to ensure good lighting of the work area. The back of the refrigerator is often covered in a layer of dust, so it is recommended that you carefully vacuum or wipe down the area around the motor before starting work. Dust and dirt can cause a short circuit or simply interfere with visual inspection of contacts and wires.
Do you need a special tool for inverter compressors?
For a basic check of the integrity of the windings of a Samsung inverter compressor, you do not need a special tool - just a multimeter. However, to fully diagnose the operation of the electronics (control board), you will already need an oscilloscope or a special inverter tester, which is only available in service centers. With a multimeter, you will only check the hardware, but not the operating logic of the board.
Removing the protective panel and accessing the compressor
The process of accessing compressor in Samsung refrigerators usually does not cause difficulties. The unit must be moved away from the wall, providing free access to the rear wall. Be sure to disconnect the device from the electrical network - remove the plug from the outlet. Working under voltage is strictly prohibited.
On the back wall you will see a metal panel covering the compressor and condenser. It is secured with several screws around the perimeter. Use the appropriate screwdriver to unscrew them. Be careful: the screws may be covered with paint or rust, so be careful not to tear off the caps.
After removing the panel, you will have a view of the lower part of the refrigeration circuit. You will see a black cylindrical or pear-shaped object - this is the motor-compressor. Next to it there is usually a plastic box (start relay) and a fan (in models with No Frost). Carefully inspect the wires going to the compressor: they should not be melted, cut or have traces of oxidation.
| Element | Location | Function | Visual sign of malfunction |
|---|---|---|---|
| Compressor | Lower part, rear | Refrigerant circulation | Strong heating, traces of oil |
| Start relay | Side on compressor | Starting the engine | Blackening, burning smell inside |
| Thermal relay | On the relay or motor housing | Overheat protection | Bloating of the housing, lack of continuity |
| Capacitor | Next to the relay (not always) | Smoothing pulsations | Bloating, leakage of electrolyte |
If visually everything looks intact, we move on to the most important stage - electrical testing. It is the measurements of the resistance of the windings that will give an accurate answer about the condition of the engine.
Checking the integrity of the windings with a multimeter
This is the most critical diagnostic stage. There are three contacts on the compressor housing, covered with a plastic cover for the start relay. Carefully remove the relay (it may be secured with clips or screws) to gain access to the terminals. They are usually arranged in a triangle.
Switch the multimeter to resistance measurement mode (Ohm, limit 2 kOhm or 200 Ohm). First check the compressor housing for breakdown. Press one probe against any copper fitting (tube) or stripped part of the body, and with the second touch all three contacts in turn. The device should show infinity (one in the left digit). If you see any resistance values, it means that there is a breakdown in the case, and the motor is faulty.
⚠️ Attention: The presence of resistance between the contacts and the case means that using such a refrigerator is deadly. The compressor needs to be replaced.
Next, we check the resistance between the contacts themselves. In classic single-phase Samsung compressors you will find three pairs of values:
- 🔌 Between the starting and working windings (total resistance).
- 🔌 Between the starting and common terminal (highest resistance).
- 🔌 Between the working and common terminal (least resistance).
Normal resistance values for different models may vary, but usually they are in the range from 10 to 60 ohms. The main rule: the sum of the resistances of the two smaller values must be equal to the largest. If the device shows zero (short circuit) or infinity (break) on any of the pairs of contacts - the compressor burned out.
Diagnostics of the starting relay and thermal protection
It often happens that the motor itself is working, but the refrigerator does not work because of a cheap part - start relay. This device provides the initial impulse to start the rotor. Samsung refrigerators often use PTC (posistor) or induction relays. Remove the relay from the housing and inspect it.
Shake the relay next to your ear. If something rattles inside, like the seeds in a maracas, it means that the posistor has crumbled due to overheating. This element requires replacement. Also inspect the inside of the relay for blackened or melted contacts. The thermal relay (protection) should “ring” (show zero) in a cold state.
To check the thermal protection, ring it with the probes of a multimeter. The resistance should be close to zero. If the device shows a break, the protective device has triggered and does not return to its original state, or has burned out. In this case, the compressor will not start, even if it is fully operational. Replacing the relay and thermal protection is a simple and inexpensive procedure.
Features of checking Samsung inverter compressors
Owners of modern models Samsung Digital Inverter should know: checking their compressors has its own nuances. These motors do not have a classic starting relay, as they start smoothly using a frequency converter. Direct connection to a 220V network for testing (as is done with conventional motors) for them is strictly prohibited will lead to instant failure.
Checking the windings of an inverter motor is done in the same way: we measure the resistance between the contacts. However, the values may be different and the pin locations may be different. Usually these are 3 contacts in a row or in a triangle, but without an external relay “pill”. The most important step here is to check the inverter board located at the bottom of the refrigerator.
If the multimeter shows normal winding resistance, but the compressor is silent, in 90% of cases the control board or the inverter unit itself is faulty. It is difficult to repair such electronics yourself without circuit design and experience. In such cases diagnosis comes down to excluding breakdown of the windingsso that the master can safely change the electronics without fear of burning the new board.
Typical errors in self-diagnosis
Home craftsmen often make mistakes, which lead to unnecessary costs. One of the most common is replacing the compressor due to a faulty thermostat or a freon leak. If there is no pressure in the system, the motor may idle or overheat, but this does not mean that it is mechanically broken.
Another mistake is ignoring the condition of the wiring. Oxidized contacts in the connector going to the compressor create high contact resistance. The motor receives less voltage, hums, heats up and turns off due to thermal protection. The owner thinks that the motor has burned out, changes it, and a month later history repeats itself.
Do not forget that after replacing the compressor or any work with the pipes, the system must be evacuated and recharged with refrigerant. You cannot simply “top up” freon - this will lead to the formation of an ice plug and failure of the new compressor. If you do not have a pressure gauge station and a vacuum pump, limit yourself to diagnosing the electrical part only.
Is it possible to start a compressor directly without a relay?
Theoretically, a single-phase compressor can be started directly by applying voltage to the working winding and briefly to the starting winding. But this is not necessary for diagnostics - just checking with a multimeter is enough. For inverter models, starting directly is impossible without a special controller.
What to do if the compressor hums, but does not start?
If you hear a hum, but does not start, first check the starting relay. If it is working properly, the compressor piston group may have jammed. Sometimes “wedging” by applying increased voltage through a special unit helps, but this is a risky procedure. Most often, when the unit is jammed, replacement of the unit is required.
How many ohms should the winding resistance show?
There is no exact figure for all models. For low-power refrigerators, the resistance of the working winding can be 20-30 Ohms, the starting winding - 40-60 Ohms. The main thing is that there is no break (infinity) or short circuit (0 Ohm), and that there is no breakdown on the housing.
Is it possible to repair a burnt-out compressor?
At home - no. Rewinding windings requires special equipment, opening the housing, soldering in an inert gas environment and assembly. The cost of such repairs will exceed the price of a new compressor. A burnt-out motor can only be replaced.
Why does the new Samsung compressor not start?
The reasons may be incorrect connection of the wires, a malfunction of the starting relay (if it was not included in the kit), a freon leak (the protection is activated) or a malfunction of the thermostat/control board. It is also important to let the refrigerator stand for at least 4-6 hours after transportation before turning it on.
Is it dangerous to change the compressor yourself?
It is dangerous not so much with electricity (with the plug disconnected), but with working with the refrigerant. There is pressure in the system. Improper soldering may result in an explosion or fire. In addition, the release of freon into the atmosphere is harmful to the environment. Technically, it is better to entrust the replacement to licensed professionals.