The situation when the refrigerator LG stops cooling food, and room temperature is set inside, always takes you by surprise. Most often, owners notice a problem when the chamber becomes warm, and the unit itself operates absolutely silently or, conversely, makes strange clicks without starting the engine. In most cases, the root of evil lies in compressor the heart of the cooling system, which for some reason refuses to start.
The absence of a characteristic hum of the motor does not always mean that the engine itself has burned out. Often the problem lies in the power circuits, starting equipment, or a trivial power surge that knocked out the protective mechanism. Understanding exactly how your refrigerator behaves when it tries to start will help you more accurately determine the malfunction before the technician arrives. LG at the time of the startup attempt, it will help to more accurately determine the malfunction before the technician arrives.
In this article we will analyze in detail the main reasons why it may not turn on, and what steps you can take yourself to diagnose. motor-compressor may not turn on, and what steps you can take to diagnose it yourself.
Primary diagnostics: analysis of the behavior of the refrigerator
Before disassembling the back wall, it is necessary to conduct a visual and auditory inspection. If the refrigerator LG is silent, listen carefully. Sometimes the engine tries to start, makes a short humming sound and goes silent, and after a while a characteristic click is heard. This behavior indicates that starting relay is trying to start the engine, but the current in the windings reaches critical values, and the protection opens the circuit.
In another case, the unit may simply stand still, although the light inside is on and there is an indication on the control panel. This suggests that the electrical signal simply does not reach the motor. Perhaps the thermostat or electronic control module has failed and simply does not give the command to start. In such cases, it is important to check whether the “Vacation” or “Eco” mode is set, which sometimes blocks the operation of the compressor in certain models. LG.
⚠️ Attention: If you hear a burning smell or see melted plastic in the compressor area, immediately unplug the refrigerator from the outlet and do not try to turn it on again until the cause of the short circuit is eliminated.
It is also worth paying attention to the temperature the housing of the compressor itself. If it is hot, it means that there was an attempt to start, but the motor jammed or it overheated. If the case is cold and the refrigerator has not been working for several hours, the problem is most likely the lack of voltage on the windings.
Faults in the start-up relay and thermostat
One of the most common reasons why the compressor in refrigerators does not start LG, is the failure of the starting relay. This small unit is responsible for supplying a starting pulse to the starting winding of the motor. Over time, the contacts inside the relay oxidize or burn, and the bimetallic plate loses its properties, ceasing to close the circuit at the right moment.
The second important element is the thermostat (or temperature sensor in models with No Frost). If this device is “stuck” in the “open” position, it simply does not transmit a signal to the control module or directly to the relay about the need for cooling. As a result, the compressor is operational, but no one gives the “Start” command. In older models LG mechanical thermostats often fail due to freon leakage from the bellows tube.
- 🔌 Failure symptoms relay: a click is heard when plugged in, the motor hums for 3-5 seconds and turns off, restarting is possible only after cooling.
- 🌡️ Signs of a thermostat malfunction: the control knob rotates without clicks, the refrigerator does not turn on even at the maximum cold setting.
- 💡 Visual inspection: on the relay body there may be traces of soot, melting or a characteristic smell of burnt insulation.
Replacing the start relay is a procedure that is often performed independently. It is enough to remove the old assembly from the three pins of the compressor and install a new one, strictly observing the marking Start, Run and Common. However, if the situation has not changed after replacement, the problem lies deeper.
Problems with electrical wiring and control module
If everything is in order with the relay and thermostat, it is worth checking the integrity of the electrical circuits. In refrigerators LG wires can rub due to vibration of the case or burn out at the soldering points. Particular attention should be paid to the wires going to the compressor itself, since in this area the temperature is often elevated.
In modern models with electronic control, control module (board) is responsible for starting the engine. If moisture gets on the board or a voltage surge occurs, the triacs or tracks that control the compressor may burn out. In this case, the indication on the panel may light up, but no commands are sent to the motor. Diagnostics of the board requires a multimeter and skills in working with electronics.
⚠️ Attention: Before testing the circuits with a multimeter, make sure that the refrigerator is completely disconnected from the power supply. Testing voltage under load without proper experience may result in electric shock.
It is also worth checking the outlet and extension cord, if used. Sometimes a simple loss of contact in the plug or low voltage in the network (below 190 Volts) prevents the compressor from starting, especially if it has worn out bearings or problems with the windings. For old houses with an unstable network, installing a voltage stabilizer can be a solution to the problem.
☑️ Electrical diagnostics
Mechanical wear and jamming of the compressor
The most unpleasant scenario is a mechanical breakdown of the compressor motor-compressor. Inside the sealed casing there is an engine and a piston group operating in oil. Over time, the oil can thicken, lose properties or leak, which leads to dry friction and jamming of the pistons.
If the compressor is stuck, it emits a dull hum when it tries to start, and then the protective relay clicks. In some cases, you can “unlock” the motor by applying increased voltage to it with a short pulse, but this method does not always work and requires special equipment. In models LG with inverter compressors, mechanical wear is less common, but the electronics of such motors are more sensitive to voltage drops.
Another reason for failure may be a break in the internal winding of the motor. If the working winding burns out, the motor will not start at all. If it is starting, it will hum, but not spin. You can check the integrity of the windings with a multimeter by measuring the resistance between the contacts on the compressor body.
| Type of fault | Winding resistance | Sound when turned on | Probability of repair |
|---|---|---|---|
| Winding break | Infinity (1) | Silence | Motor replacement required |
| Interturn short circuit | Below normal | Humming, knocks out plugs | Motor replacement required |
| Stuck | Normal | Humming and clicks | Attempt to wedge or replacement |
| Relay malfunction | Normal | Clicks, short hum | High (relay replacement) |
Is it possible to replace the compressor yourself?
Theoretically yes, but this requires a vacuum pump, a pressure gauge station, a torch and skills in soldering copper pipes. In addition, it is necessary to charge the refrigerator with the exact amount of freon. Without special equipment and a license to work with refrigerants, high-quality repairs are impossible.
Specifics of LG inverter compressors
Refrigerators LG are often equipped inverter compressorsthat do not operate according to the principle “turned on and off”, and smoothly regulate the power. If such a compressor does not work, diagnostics become much more complicated. There is no classic starting relay here, and the start is carried out by a special inverter unit.
The reasons for the failure of the inverter motor may be associated with a malfunction of the inverter itself (the control board, often located on the compressor itself or at the bottom of the refrigerator). The self-diagnosis system LG can block startup if an error is detected in the temperature sensors or current leakage.
In such models, it is important to pay attention to error codes that may appear on the display or blink indicators. For example, a combination of flashes may indicate a communication error between the main board and the inverter. It is difficult to decipher these signals without a service manual.
⚠️ Attention: Inverter compressors are sensitive to the quality of power supply. Using cheap surge protectors instead of full-fledged stabilizers can lead to failure of expensive electronics.
If you are the owner of a refrigerator with an inverter motor and it has stopped cooling, self-repair is limited to checking the power supply and contacts. In-depth diagnostics require connecting a service tester.
Algorithm of actions and when to call a technician
To summarize, you can draw up a clear action plan for the owner of the refrigerator LG. If the unit does not turn on, start by checking the network voltage and the absence of standby modes. Then listen to the motor: silence, hum or clicks will indicate the direction of search.
If you find that the starting relay is black and smells like burning, you can replace it yourself by choosing an analogue. If the engine is hot but silent, or hums and knocks out the machines, the situation requires the intervention of a professional. A technician is also needed if the compressor itself needs to be replaced, since this involves working with refrigerant and a sealed circuit.
You should not delay repairs if the refrigerator has stopped freezing. Prolonged downtime can lead to defrosting of food and damage to the evaporator due to moisture entering the system during depressurization. Timely diagnostics will save your budget and products.
Is it possible to revive an old LG compressor?
There is a method of “wedging” by impact or applying increased voltage, but its effectiveness is less than 30% and is temporary. In 70% of cases, the engine either does not start or jams again after a month. It is more economically feasible to replace the unit.
How much does it cost to replace a compressor in an LG refrigerator?
The cost consists of the price of a new motor, replacement work, evacuation of the system and refilling with freon. On average, this ranges from 40% to 60% of the cost of a new refrigerator. For older models, repairs may not be cost-effective.
Why does the compressor turn on and then immediately turn off?
This is the work of a thermal protection relay. It opens the circuit because the current in the motor windings exceeds the norm. Reasons: jammed motor, faulty start relay, turn-to-turn short circuit or critically low voltage in the network.