Modern household appliances of the brand LG are famous for their reliability and the introduction of innovative technologies, such as Linear Inverter. However, even the most advanced units are not immune to the appearance of extraneous acoustic effects that may alert the owner. Strange sounds that occur during operation are often the first signal about the need for diagnostics or preventive maintenance.
Do not panic when you hear an unusual hum or periodic clicks. In most cases, these manifestations are associated with physical processes occurring inside the cooling system, or are a variant of the norm for certain operating modes. Understanding the nature of the origin of sounds will allow you to distinguish normal operation from a serious malfunction that requires the intervention of a specialist.
In this article we will analyze in detail the mechanics of the occurrence of various noises characteristic of Korean-made refrigeration equipment. You will learn how to independently identify the source of the problem, when to sound the alarm, and when it is enough to simply wait for the defrost cycle to complete or the temperature to stabilize.
Acoustic features of the operation of an inverter compressor
The main source of sound in any refrigerator is the compressor unit. In models LG often installed linear inverter compressorsthe operating principle of which is radically different from classic piston analogues. Instead of constant cycles of on and off at full power, such a motor smoothly regulates its performance, which in theory should ensure silence, but in practice creates a specific acoustic background.
A characteristic low-frequency hum or quiet hum, which can either subside or intensify, is an absolutely normal phenomenon for an inverter system. This indicates that the electronics control the engine rotation speed depending on the current load and temperature inside the chambers. If the sound is uniform and does not cause vibration of the housing, there is nothing to worry about.
However, if the hum turns into an increasing roar or is accompanied by a metallic clanging, this may indicate wear of the bearings or problems with the fastening of the unit itself. Vibrationtransmitted to the floor or walls often enhances this effect, creating the illusion of louder operation equipment.
⚠️ Attention: If the hum of the compressor suddenly changes its tone and is accompanied by frequent startup attempts followed by a click and shutdown, immediately disconnect the device from the network. This may be a sign of an interturn short circuit or jamming of the mechanism.
Refrigerant sounds: gurgling, pouring and hissing
One of the most common causes of concern for owners is the sound of the refrigerant moving through the system pipes. Freon circulating in the circuit can make sounds reminiscent of water pouring, gurgling or a quiet hiss. These manifestations are especially noticeable in the first hours after turning on or loading a large amount of warm products.
The physics of the process is simple: in the liquid phase the refrigerant is almost silent, but when passing through the capillary tube and entering the evaporator, part of the substance boils, forming a gas. It is this process of boiling and mixing of phases that causes the characteristic “gurgling” sound. In models with the system No Frost sounds may be more audible due to the complex air duct system.
Often users notice that after opening the door the sounds become louder. This is due to a sharp pressure drop and the entry of warm air, which forces the cooling system to work harder, accelerating the flow of refrigerant. Also, hissing can occur when the pressure in the system equalizes after stopping the engine.
Why are sounds heard at night?
At night, extraneous noises seem louder due to the general silence in the apartment. In addition, at night the voltage in the electrical network may decrease, which slightly changes the nature of the operation of electric motors, making their sound more noticeable at low frequencies.
Clicks and crackles: operation of the automatic defrosting system
Periodic clicks, reminiscent of finger strikes on plastic or slight crackling, are most often associated with the operation of the system automatic defrosting. In refrigerators LG with technology Total No Frost this process is started by a timer several times a day to prevent the formation of an ice coat on the evaporator.
During defrosting it turns on TEN (thermoelectric heater), which heats the evaporator. The sharp expansion and contraction of plastic parts of the housing, air ducts and the evaporator itself under the influence of temperature changes causes a characteristic crackling sound. This phenomenon is known as “thermal expansion” and is considered normal.
The thermostat or sensors that open and close the electrical circuit can also make clicks. If the clicks are infrequent (every few hours) and are not accompanied by other alarming symptoms, no maintenance is required. The sound should be short and clear.
| Sound type | Probable cause | Normal or malfunction |
|---|---|---|
| Uniform humming | Inverter compressor operation | Normal |
| Gurgling of water | Movement of freon in the tubes | Normal |
| Loud crackling of plastic | Thermal expansion at defrosting | Normal |
| Metal clanging | Destruction of compressor parts | Fault |
| Whistling or squeaking | Fault fan | Malfunction |
Problems with fans in No Frost systems
Refrigerators LGequipped with a forced air circulation system have one or two fans: in the freezer and refrigerator compartments. These devices ensure even distribution of cold. Over time, malfunctions may occur in their operation, which are expressed in the appearance of a whistle, howl or hum.
The most common reason for the appearance of extraneous sounds is ice freezing on the fan blades or on the axis of its rotation. Ice may form due to a leak in the door seal or a malfunction of the condensate drainage system. The blades, touching the ice crust, emit a rhythmic knock or crackling sound, the frequency of which depends on the rotation speed.
Another reason may be wear of the plain bearings of the fan itself. In this case, the sound will resemble a monotonous hum or howl, which stops if you open the refrigerator door (since in many models the fan stops when the door is opened). To eliminate this, you will need to replace the unit.
☑️ Fan diagnostics
Vibration of the case and resonance with external objects
Sometimes the source of noise is not inside the unit, but outside. The vibration that occurs during compressor operation can be transmitted to the refrigerator body, and then to the floor, walls or nearby objects. This causes a resonance effect that greatly amplifies even quiet sounds.
Check that the refrigerator is not touching furniture, walls or other household appliances. Even a minimum gap of 1-2 centimeters is necessary for free air circulation and no rattling. Also make sure that there are no unstable bottles or dishes on the top cover or shelves inside that could jingle due to microvibration.
It is important to check that the transport fasteners are installed correctly. Although in modern models LG it is often represented by plastic clips that are easy to notice, in some cases users forget to remove the spacers inside the compressor compartment or the fixing brackets on the rear wall.
⚠️ Attention: Do not install the refrigerator in a niche without gaps. Manufacturers require a minimum distance to the side walls and ceiling for effective heat transfer. Violation of this rule leads not only to noise, but also to overheating and breakdown of the compressor.
Mechanical faults and wear of parts
If all normal causes are excluded, it is worth considering the possibility of mechanical breakdowns. Aging of materials, wear of rubbing parts and imbalances can lead to sounds that cannot be ignored. In such cases, operation of the equipment may be unsafe.
Critical malfunctions include destruction of the compressor suspension. The engine is mounted on springs or rubber shock absorbers that dampen vibration. If the rubber has dried out and burst, and the springs have lost their elasticity, the compressor begins to hit the metal walls of the housing or frame, producing a loud metallic knock.
It is also worth paying attention to the condition of the condensate collection tray located above the compressor. If it is loose or cracked, it will rattle from the vibration of the motor. Often it is enough to place a piece of foam rubber or rubber to eliminate this defect.
Frequently asked questions (FAQ)
Is it normal for a new LG refrigerator to hum loudly in the first days?
Yes, this is quite normal. A new compressor needs time to break in. In the first 2-3 weeks of operation, the noise level may be higher than usual, and the sounds of refrigerant overflow may be more distinct. This is due to the grinding in of parts and filling the system with oil.
Why does the refrigerator make a popping sound when turned off?
A sound similar to a pop or a loud click when the compressor stops is caused by equalizing the refrigerant pressure in the system. Gases flow from a high pressure zone to a low pressure zone, which creates an acoustic effect. This is a characteristic feature of many modern refrigeration units.
Can a sound indicate a freon leak?
A freon leak itself usually does not produce loud sounds, except for a possible hissing sound at the site where the tube is damaged (which happens extremely rarely and requires immediate shutdown). However, if the leak has led to air in the system, the nature of the gurgling may change, becoming more constant and loud.
What to do if the refrigerator begins to vibrate and “ride” on the floor?
It is urgent to check the adjustment of the support legs. Most likely, one of them is unscrewed too much or, conversely, does not reach the floor, which is why the body is skewed. Also check that the transport wheels or stands have not been removed, if they were provided for in the design.