The situation when a refrigerator begins to make unusual sounds is familiar to many owners of household appliances. Extraneous noise can vary from a barely audible hum to a loud knock that can wake up people. nights. Users often panic ahead of time, believing that the unit has failed, but not all sounds indicate a breakdown.
Modern models, be it LG, Samsung or Bosch, are equipped with complex refrigerant circulation systems and compressors operating under high pressure. Understanding the physics of the processes occurring inside the case will help you distinguish normal operation from a real malfunction that requires the intervention of a specialist.
In this article we will analyze in detail the mechanical, thermal and electrical causes of noise. You will learn to determine the nature of the sound and localize the source of the problem in order to make the right decision on further actions.
Natural sounds of a working refrigerator
Before sounding the alarm, you need to make sure that the observed noise is not the normal operating mode of the equipment. New models often emit sounds that were absent in older units, which is associated with the introduction of new energy-saving technologies and No Frost systems. One of the most common phenomena is liquid overflow. This sound occurs in the evaporator and condenser tubes, where the refrigerant changes its state of aggregation, moving from liquid to gaseous and back. Even if the refrigerator is perfectly level, this process is accompanied by a characteristic acoustic effect.
One of the most common phenomena is gurgling or fluid transfusion. This sound occurs in the evaporator and condenser tubes, where the refrigerant changes its state of aggregation, moving from liquid to gaseous and back. Even if the refrigerator is perfectly level, this process is accompanied by a characteristic acoustic effect.
⚠️ Attention: If gurgling is accompanied by a complete lack of cold in the chambers or continuous operation of the motor without shutdowns, this may indicate a freon leak. In normal mode, the sound of circulation is heard periodically.
Periodic crackling plastic or metal is also considered normal. The materials from which the internal walls and the casing box are made have different coefficients of thermal expansion. If there is a sudden change in temperature, for example, immediately after turning on or off the compressor, parts may become slightly deformed, producing clicking noises.
Many users mistake the operation of the system for a breakdown. No Frost. These models have a fan installed that circulates air around the chamber. Its uniform hum is not a sign of malfunction, but a necessity to ensure proper circulation of flows and prevent the formation of ice.
Mechanical reasons: vibration and unstable position
If you hear a low-frequency hum or rattling that is transmitted to the floor and furniture, the problem most likely lies in the physical position of the unit. Vibration is the main enemy of silence, and often it is caused by a banal violation of installation rules.
The first thing that needs to be checked is the adjusting supports. If the refrigerator is not level, one of the legs may not touch the floor, creating a misalignment. As a result, the housing begins to resonate when the compressor operates, amplifying any sound significantly. To diagnose, just lightly press on the upper corner of the refrigerator: if the noise changes or disappears, then the problem is stability.
The second important aspect is the distance to the walls and furniture. The rear grille of the capacitor and the housing itself should not touch the surfaces closely. A minimum gap of 5-10 cm is necessary for free air circulation and vibration damping. With close contact, the hum is transmitted to building structures, creating a drum effect.
☑️ Diagnostics of refrigerator installation
Do not forget about the internal contents. Dishes made of thin glass or plastic, standing close to each other, can ring from the slightest vibration of the shelves. Rattling often comes from loose bottles or egg trays that begin to move when the motor starts.
Compressor noises: is this normal or a sign of wear?
The compressor is the “heart” of the refrigerator, and it is the main source of noise in any model. However, the nature of the sounds it makes can tell a lot about the technical condition of the unit. A serviceable motor operates evenly, with an increasing hum when starting and fading before stopping.
If you hear loud metal clanging thumps when you turn the equipment on or off, this may indicate problems with the start relay or shock absorbers of the compressor itself. In older models, the rubber washers on which the motor is mounted often broke, causing it to start hitting the metal casing or frame.
Inverter compressors installed in modern Liebherr or Electroluxwork differently. They do not turn off completely, but only slow down. Therefore, a quiet, monotonous hum, which either intensifies or subsides, is absolutely normal for them. A loud knocking or howling in such systems already indicates a serious malfunction.
⚠️ Attention: If the compressor hums very loudly, but the cold does not gain, and at the same time it is hot to the touch, there may be a break in the internal winding or the piston group is jammed. Operation in this mode is dangerous.
You should also pay attention to the compressor casing. Sometimes the vibration is transferred to the metal casing that covers the rear of the engine. If the housing is loosened, it begins to rattle. In this case, it is enough to simply tighten the bolts or place a piece of rubber or foam rubber between the metal.
How to extend the life of the compressor?
To reduce the load on the compressor and reduce noise, try not to put hot products in the chamber. A sharp rise in temperature forces the motor to work at its limit, which increases noise and wear of parts. Also regularly clean the rear grille of dust to ensure effective heat exchange.
Problems with the defrosting system and fans
In refrigerators with a system No Frost or Frost Free additional components are responsible for air circulation and defrosting the evaporator. If you hear a whistling, grinding or crackling sound similar to a propeller, the problem may lie here.
The fan located behind the back wall of the freezer can become dirty over time or lose grease in the bearings. When ice crust accumulates on the blades, an imbalance occurs and the fan begins to make noise, touching the ice or the walls of the housing. This is often accompanied by a decrease in cooling efficiency.
Another source of sound in this system is the defrosting heating element. When heated, it may burn food residues or dust that gets onto the evaporator, which causes hissing. In addition, dripping water onto a hot heating element produces a characteristic hissing sound, which many confuse with a gas leak.
If you hear the cracking of ice, this may mean that the melt water drainage system is clogged. The water does not have time to go into the drainage tray, freezes, and then, when the heating element is turned on, the ice plug cracks or breaks off with a loud sound. In such cases, it is necessary to defrosting cleaning the drainage hole.
| Type of sound | Probable cause | Location | Repair urgency |
|---|---|---|---|
| Whistling or howling | Fan malfunction | Freezer compartment | Medium |
| Loud hissing | Water on heating element or leakage | Rear wall/Evaporator | High |
| Ice cracking | Defrosting cycle | Inside the chamber | Not required |
| Knock of blades | Ice on the fan | Freezer compartment | Medium |
Hydraulic hammer and problems with refrigerant
One of the most unpleasant problems that causes strong shocks inside the system is the so-called hydraulic hammer. This occurs when liquid refrigerant instead of gaseous refrigerant enters the compressor cylinder. The liquid does not compress, and the piston hits the valve group with force, producing a loud metallic knock.
The reasons for this phenomenon can be different: from overcharging the system with freon (if the repair was carried out unskilled) to a malfunction of the thermostatic valve. If the refrigerator began to make such sounds after a recent repair, this is almost guaranteed to indicate a technician error.
Another symptom of problems with the refrigerant is a whistle. If you hear a thin whistling sound, especially near pipe solder joints or near the compressor, this may indicate a problem in the circuit. Gas escapes through it under pressure. This is a critical situation that requires immediate shutdown of the device. microcrack in the circuit. Gas escapes through it under pressure. This is a critical situation that requires immediate shutdown of the device.
It is important to note that modern refrigerators use mixtures of gases that may have an odor. If a specific chemical smell is added to the whistle, the room must be ventilated urgently, since some refrigerants in high concentrations are harmful to health.
When noise indicates a critical breakdown
There are a number of sound signals, ignoring which can lead to complete failure of the equipment or even a fire. If your refrigerator makes sounds described below, operation should be stopped.
The first alarm signal is loud crackling, similar to an electrical discharge, accompanied by flashing lights in the room. This indicates a breakdown of the wiring insulation or a malfunction of the starting relay, which sparks. Further connection to the network may lead to a short circuit.
The second sign is a continuous, increasing hum of the compressor, which does not stop for hours. If the refrigerator does not freeze, but the motor is hot, it means that it is running “idle” due to loss of refrigerant or compression. This leads to rapid burnout of the motor windings.
⚠️ Attention: If you hear a sound like an explosion or a strong bang, and smell a burning smell, immediately unplug the cord from the outlet. This may indicate a capacitor explosion or a wiring fire.
You should also be wary if a metallic ringing is added to the standard hum, which intensifies over time. This may indicate that valves or bearings have collapsed inside the compressor, and metal (shards) are circulating in the oil, destroying the mechanism from the inside.
Methods for eliminating noise and prevention
Most noise problems can be solved independently, without resorting to the costly services of a service center. The main thing is to act consistently and follow safety precautions. Before any manipulations inside the cameras, be sure to disconnect the device from the network.
Start with a simple revision of the contents. Move the bottles away from each other, check that the products are not touching the back wall. If the noise is caused by vibration, try placing special anti-vibration pads or a piece of thick rubber under the feet. This often works wonders on noisy models.
If the problem is with the fan, the refrigerator will need to be defrosted for 10-12 hours. Often the ice frozen on the fan axis melts and silent operation is restored. If the bearing is worn out, the fan will have to be replaced, which requires disassembling the rear panel of the freezer.
To reduce noise from the compressor, you can use soundproofing materials. Special self-adhesive bitumen sheets or technical cork material can be glued to the inside of the metal motor casing. This will reduce the resonance and make the hum less noticeable.
Why does the refrigerator make sounds only at night?
During the day, extraneous noises (street noise, conversations, TV) mask the operation of the equipment. At night, in silence, even the standard hum of the compressor or the gurgling of freon becomes audible. If the sound has not changed in character, but has simply become more noticeable, this is normal.
Is it dangerous if the refrigerator clicks but does not turn on?
Frequent clicks without starting the motor usually indicate a malfunction of the start relay or the compressor itself (jamming). This is not dangerous for residents, but it is better to turn off the equipment so as not to completely burn out the wiring or relay.
Is it possible to lubricate a refrigerator fan?
Most modern models have maintenance-free plain bearings. Trying to lubricate them with oil may cause the plastic to break or the lubricant to spread onto the windings. If noise appears, it is better to replace the fan with a new one.
Is it normal that a new refrigerator is noisier than the old one?
Yes, modern compressors can operate at higher speeds to quickly reach the operating mode, and thin walls of cases insulate sound worse. In addition, new cooling systems are more complex and can produce a wider variety of sounds.
How to check if the refrigerator is vibrating against the wall?
Move the refrigerator 15-20 cm from the wall. Turn it on. If the nature of the noise has changed or vibration has ceased to be transmitted to the furniture, the problem was insufficient clearance. Install limiters on the legs to control the distance.