Situation, when LG refrigerator buzzes without interruption, is familiar to many owners of this equipment. Instead of the usual on and off cycle, the compressor works non-stop, trying to reach the set temperature. This not only leads to a significant increase in electricity bills, but also creates constant background noise that can irritate household members.
Constant operation of the motor is a serious signal that cooling system is not doing its job. At best, the problem lies in incorrect installation or a minor malfunction that you can fix yourself. At worst, we are talking about the breakdown of key components, requiring the intervention of a professional technician.
In this article we will analyze in detail why unit it goes into emergency operation mode. We will consider both external factors and internal failures characteristic of models LG No Frost and classical systems. Understanding the reasons will help you make the right decision: try to repair the equipment yourself or immediately call a specialist.
External factors and improper operation
Before you panic and look for the service center number, you should exclude trivial reasons. Often Continuous operation the compressor is caused not by a breakdown, but by a violation of operating conditions. If the refrigerator is installed too close to a wall or heat sources, the heat dissipation efficiency drops sharply. In such conditions, equipment has to work to the limit to compensate for the constant flow of heat.
Another common factor is sealing rubber. If it is worn out, dirty, or simply does not fit tightly to the body, warm air constantly enters the chamber. Sensors detect the temperature increase and give the command to the compressor not to stop. Check the condition of the seal around the entire perimeter of the door.
It is also worth paying attention to what exactly you store inside. Hot foodplaced on a shelf create a colossal heat load. The cooling system will produce cold until the temperature inside stabilizes, which may take a long time.
⚠️ Attention: If you have just defrosted the refrigerator or loaded it with a large amount of food at room temperature, continuous operation for 6-12 hours is normal intensive mode frosts.
Malfunctions of the thermostat and temperature sensors
One of the most common reasons why LG refrigerator does not turn off is the failure of the thermostat. This small device is responsible for controlling the temperature inside the chambers. If its contacts stick in the “on” position or it loses sensitivity, the compressor receives a false signal that the chamber is warm and continues to work.
In modern models with the system No Frost electronic sensors (thermistors) are responsible for this process. Their readings are read control module. If the sensor “lies” and shows, for example, +10°C instead of the real +4°C, the electronics will keep the motor on. Replacing the sensor is not a complicated procedure, but requires accurate diagnostics with a multimeter.
Sometimes the problem lies not in the sensor itself, but in oxidation of the contacts or breakage of the wiring going to it. In this case, the signal simply does not reach the board, and the system goes into emergency mode of constant operation to avoid defrosting the products.
To check the mechanical thermostat, you can try to gently knock on its body or temporarily replace it with a known good one. Electronic sensors are checked only by measuring resistance at different temperatures.
How to check a thermostat with a multimeter?
To check a mechanical regulator, remove the terminals from it and ring the contacts. At room temperature the circuit should be closed (the multimeter beeps). If you put the regulator in the freezer for 15 minutes, the circuit should open. The absence of changes indicates a malfunction.
Problems with the defrost system in No Frost refrigerators
If your LG No Frost refrigerator buzzes non-stop, but cools weakly, most likely the problem lies in the evaporator defrost system. In such models, ice frozen on the radiator blocks the circulation of cold air. The compressor works, trying to cool the chamber, but the cold simply does not reach the food.
The main culprits here are three elements:
- 🧊 defrost heating element —a heating element that could have burned out and stopped melting the ice.
- 🔌 Defrost relay — a device that supplies voltage to the heating element; if it breaks, the heating does not turn on.
- 🌡️ Defrost sensor — tells the control module when to turn the heating on or off; if it is faulty, the defrost cycle will not start.
Visually, this problem can be diagnosed by moving the refrigerator and removing the back panel in the freezer. If you see a massive piece of ice or frost blocking the air ducts there, the diagnosis is confirmed. Until the ice is completely removed and the system is repaired, compressor will work around the clock.
⚠️ Attention: When defrosting the evaporator in the No Frost system, it is strictly forbidden to use sharp objects (knives, screwdrivers) to chip ice. You can damage the circuit tubes or the evaporator itself, which will lead to a freon leak.
Refrigerant leaks and compressor malfunctions
The most serious and expensive reason for continuous operation is freon leak. If a microcrack forms in the refrigerant circuit, the gas gradually escapes. The pressure in the system drops, and the compressor, trying to compensate for the lack of cooling capacity, begins to work without stopping. However, even in this mode, it will not be able to reach the desired temperature.
Signs of a leak are often accompanied by additional symptoms:
- ❄️ The freezer is working normally, but in the refrigerator compartment the temperature is higher than normal.
- 🔥 The side walls of the refrigerator remain cold (normally they should warm up slightly).
- 🔊 The compressor operates louder than usual or gurgling and hissing can be heard.
It is also worth mentioning interturn short circuit in the windings of the compressor itself. In this case, the motor loses power and cannot create the necessary pressure while idling. Repair in this case usually involves a complete replacement of the compressor, since rewinding is not economically feasible.
Clogged capillary tube and problems with the filter
Another technical malfunction leading to non-stop mode is clogging of the capillary tube. This thin copper tube serves as a choke, separating the high and low pressure zones in the system. Over time, oil oxidation products or moisture may accumulate in it, turning into an ice plug.
When the permeability of the tube is impaired, the circulation of freon becomes difficult. The pressure at the outlet of the compressor increases, the motor begins to work with overload and does not turn off, since the sensors in the chamber do not detect sufficient cooling. This is often accompanied by overheating of the compressor housing.
To eliminate this problem it is required:
- The system is evacuated to remove moisture.
- The circuit is purged with nitrogen under pressure.
- Replaced filter drierwhich retains moisture and dirt.
This procedure requires specialized equipment (vacuum pump, pressure gauge station, nitrogen cylinder) and skills in soldering copper pipes. It is almost impossible to carry out high-quality repairs on your own without experience.
Comparative table of symptoms and causes
To make it easier for you to navigate a possible malfunction, we have compiled a summary table. It will help compare the behavior of your LG refrigerator with typical signs of breakdowns.
| Symptom | Probable cause | Complexity repair | Need a technician |
|---|---|---|---|
| The refrigerator hums, but does not freeze | Freon leak or compressor failure | High | Required |
| Works without stopping, it’s warm inside | Thermostat or sensor is faulty | Medium | Desirable |
| Freezer in ice, cold does not enter the chamber | Malfunction of the defrost system (No Frost) | Average | You can do it yourself |
| Works constantly after loading products | Violation of the rules operation | Absent | Not required |
| The compressor is hot, gurgling can be heard | Clogged capillary system | High | Required |
What you absolutely cannot do
When trying to solve the problem on their own, owners often commit errors that turn a simple repair into a complex and expensive procedure. For example, some try to “help” the compressor by installing additional fans outside or changing the thermostat settings to maximum.
Never try to solder the circuit tubes with regular solder without using nitrogen purge - this is guaranteed to lead to a new blockage of the system. Also, you should not ignore the problem in the hope that it will “go away on its own.” Overheating of the windings of the compressor during prolonged operation without stopping can lead to a short circuit and fire.
⚠️ Attention: Do not leave the refrigerator operating in emergency mode unattended at night or when leave home. The risk of electrical wiring fire or insulation melting in this state increases significantly.
☑️ Diagnostics before calling a technician
When you need to call a specialist
If you checked seals, defrosted the chamber and made sure that the equipment is installed correctly, but LG refrigerator continues to work without interruption, it’s time to call service. This is especially true if you do not have experience working with electrical circuits and refrigeration equipment.
A professional technician will conduct diagnostics using pressure gauges, check the compressor current consumption and the tightness of the circuit. Repair of refrigeration equipment is not only the replacement of parts, but also the correct filling of freon of a certain type and in a strict quantity.
Remember that modern models LG equipped with complex electronics. Misdiagnosis can lead to replacing a working control board when the problem was in a cheap sensor. A qualified approach will save you money in the long run.
How much does a repair cost?
The cost depends on the region and model. Replacing the thermostat is usually cheaper than refilling with freon or replacing the compressor. The technician will name the exact price only after on-site diagnostics.
FAQ: Frequently Asked Questions
Can an LG refrigerator work without interruption in the summer?
Yes, in hot weather (+30°C and above), the compressor operating time increases and the standstill time is reduced. However, it should still turn off periodically. If the on-off cycle completely disappears, this is a malfunction.
How long does it take for the refrigerator to get cold after defrosting?
Usually the process takes from 2 to 8 hours, depending on the model and volume of loaded products. If after 12 hours the motor does not turn off and the temperature has not reached normal, look for the cause of the breakdown.
Why does the refrigerator not turn off after replacing the compressor?
Perhaps the technician made a mistake when filling with freon (underfilling or overfilling), did not replace the filter-drier, or did not vacuum the system properly. There could also be a blockage in the circuit.
Does the "Super Freeze" mode affect continuous operation?
Yes, when the function is activated Super Freeze the refrigerator can work non-stop for up to 48 hours (or until the function is manually turned off) to quickly freeze a large volume products.
Is it dangerous to (continue to use) a refrigerator if it does not turn off?
Short-term operation is not dangerous. But long-term operation in non-stop mode (a day or more) leads to overheating of the motor, drying out of the oil and eventual combustion of the windings, which will require an expensive replacement of the unit.