An unexpected hum from kitchen appliances can ruin the mood of even the calmest person, especially if it happens at night. When the refrigerator makes a lot of noise, this is not just an irritating factor, but also a signal of possible malfunctions in the operation of the unit. Owners often panic, believing that the device is faulty and requires expensive repairs, but in half of the cases the problem is solved on its own in a matter of minutes.
In this article we will look in detail at why the refrigerator hums, how to distinguish a normal operating sound from a sign of a breakdown, and what steps need to be taken to reduce the noise level. Understanding the physical processes occurring inside refrigerator compartmentwill help you correctly diagnose the situation and avoid unnecessary expenses on calling a technician.
The primary task is to determine the source of the sound: does it come from the vibration of the case, the operation of the motor, or foreign objects. Diagnostics starts with carefully listening to the nature of the hum. This may be a monotonous hum, intermittent knocking, whistling or sharp clicks.
It is important to understand that modern models operating on inverter compressorsmake significantly less noise than their predecessors, but they are not immune to technical problems. If your unit makes sounds that were not previously characteristic of it, you cannot ignore it.
Natural causes of noise and hum during operation
Before sounding the alarm, it is necessary to exclude physiological causes, which are the norm for any cooling equipment. When compressor starts, it creates pressure in the system, which is inevitably accompanied by sound. When the motor is turned on, the refrigerant begins to actively circulate through the tubes, which can cause gurgling sounds or a slight hiss.
This effect is especially noticeable in models with the system No Frost, where the sound of a running fan is complemented by the noise of the motor. After the compressor is turned off, a quiet crackling or clicking sound may be heard - this is the result of thermal expansion and contraction of plastic parts and metal tubes as the temperature changes.
⚠️ Attention: If, after defrosting or first installation, the refrigerator makes loud noises during the first 2-3 hours, this may be due to reaching operating mode. Give the equipment time to stabilize.
It is also worth considering that the noise level directly depends on the load on the cameras. An empty refrigerator may make a louder noise due to resonance, while a tightly packed unit is quieter. The sounds of overflowing liquid in the tubes capillary system are also a variant of the norm and indicate correct circulation of freon.
Problems with installation and alignment of the case
One of the most common reasons why a refrigerator hums is a banal incorrect installation. If the unit is unstable, the slightest vibration from the running motor is transmitted to the floor and walls, creating the effect of an increased hum. In this case, vibration becomes a resonator, multiplying the sound volume.
To fix the problem, you need to check the horizontal installation. Even a slight misalignment can cause the door to not fit tightly and the body to begin to rattle. Use a building level or a regular glass of water placed on the lid to assess the position of the unit.
☑️ Checking the installation of the refrigerator
Particular attention should be paid to the distance to the walls and furniture. If the refrigerator is moved close to the wall, vibration is transmitted to building structures, and the hum can be heard even in neighboring rooms. The minimum permissible distance to the rear wall should be 5-10 centimeters to ensure normal air circulation and reduced resonance.
The adjusting supports located in the lower front part of the device allow you to compensate for uneven floors. By twisting or unscrewing these legs, you can achieve an ideal position in which the refrigerator will stand “firmly” and not wobble with a slight push.
External factors: dishes and objects on the body
Often the source of irritating rattling is not the internal mechanisms at all, but foreign objects placed on or inside the refrigerator. Any loose dishes, jars of spices or decorative elements standing on the top lid begin to vibrate in time with the operation of the compressor.
Inside the chambers the situation is similar: if the shelves are not loaded tightly or glass bottles touch each other and the walls, during operation fan they will make a ringing sound. Check that the products or containers do not touch the walls of the chamber, especially in areas of active circulation of cold air.
The condensate drainage system deserves special attention. If the drain hole is clogged or the water collection tray (located above the compressor at the rear) is not installed correctly, it may rattle due to motor vibration. Remove the back panel and check that all removable elements are securely fastened.
⚠️ Attention: Never place heavy objects on the refrigerator that could move and unbalance the case. This will not only increase the noise, but is also dangerous for the stability of the unit.
Make sure that inside the chambers all shelves and drawers are inserted all the way into the guides. The play of plastic elements during vibration creates an unpleasant plastic crack, which can easily be mistaken for a breakdown of the mechanical part.
Malfunctions of the compressor and cooling system
If external factors are excluded, and the refrigerator continues to make a lot of noise, the problem may lie in technical components. The most expensive and important part is compressor. If it is worn out, its operation is accompanied by a loud hum, knocking or even clanging. This may indicate damage to the internal valves or bearings.
In models with two compressors (separate for the refrigerator and freezer compartments), the noise may come from one of them. You can determine the source by placing your hand on the rear wall in the area of the motor - the vibration will be felt stronger where the faulty unit is located.
Symptoms of a compressor malfunction
If the humming is accompanied by overheating of the rear grille (to the point where you cannot touch it with your hand), and the motor does not turn off for hours, this is a sign of loss of performance or leakage freon.
Another cause of noise is a malfunction fan in the No Frost system. If ice builds up on the blades or dust gets into the bearing, the fan begins to hum or grind. The sound often increases when the door is opened, since in some models the fan changes rotation speed.
Cooling system pipes can also become a source of noise if they come into contact with each other or with the walls of the case. The vibration is transmitted through the tubes, and they begin to beat against the metal, creating a ringing sound. In this case, careful separation of the tubes is required, but this must be done with caution so as not to damage refrigerant.
| Type of sound | Probable cause | Degree of danger | Necessary actions |
|---|---|---|---|
| Monotonous hum | Normal compressor operation | Low | Check the installation and distance to the walls |
| Rattling | Dishes, unstable legs | Low | Remove unnecessary objects, level the floor |
| Grinding/Squealing | Fan malfunction | Average | Cleaning ice or replacing the fan |
| Loud knocking/clanging | Compressor wear | High | Call a technician, engine diagnostics |
Influence of shock absorber wear and fastenings
The compressor inside the refrigerator is mounted on special shock-absorbing springs or rubber gaskets. Over time, these elements lose their elasticity, harden or crack. As a result, depreciation is disrupted, and the vibration of the motor is transmitted directly to the body of the refrigerator.
This problem can be identified by the characteristic metallic rattling that occurs precisely at the moment the motor starts or stops. If you touch the body at the moment of switching on, you can feel a strong trembling, which should not happen with working shock absorbers.
Replacing shock absorbers is a procedure that requires disassembling the technical part of the unit. It is necessary to remove the back cover, turn off the power and carefully replace the rubber bushings or springs. The use of original spare parts guarantees the restoration of factory sound insulation parameters.
⚠️ Attention: Replacing shock absorbers yourself requires skills in working with power tools and knowledge of equipment. Inexperienced intervention can lead to damage to the tubes or a violation of the tightness of the system.
Sometimes, to temporarily reduce noise, technicians recommend placing additional rubber gaskets under the standard fasteners, but this solution is not always effective in the long term. It is better to make a full replacement of worn-out elements.
When it is necessary to call a specialist
There are a number of symptoms in which self-repair is not only ineffective, but also dangerous. If your refrigerator makes loud popping noises or smells like burnt wiring or plastic, unplug it immediately. This may indicate a short circuit or overheating of the electric motor.
Also, a reason to call a specialist is a situation where the refrigerator has stopped freezing, but is noisier than usual. This is a classic sign of a freon leak or a clogged capillary system when the compressor runs “idle”, trying to build up pressure.
You should not try to repair the sealed system (soldered circuit) yourself. To work with refrigerant special equipment and a license are required. Attempts to solder tubes or add gas yourself can permanently damage the unit.
A professional technician uses special instruments to measure pressure and noise levels, which allows you to accurately determine the source of the problem. In some cases, it is cheaper to replace an old noisy compressor with a new one, less powerful, but quieter and more economical.
Prevention and operating rules
In order for the refrigerator to operate quietly and for a long time, it is important to follow the operating rules. Regular defrosting (for drip systems) prevents the formation of ice plugs, which can interfere with the operation of the fan and create noise. No Frost systems also require periodic defrosting at least once a year to clear hidden ice.
Keep the condenser grill at the back of the refrigerator clean. Dust and pet hair that accumulates between the coils impair heat transfer, causing the compressor to work harder and longer, which increases the overall noise level.
How often should you wash the refrigerator?
It is recommended to carry out external cleaning once a week, and complete defrosting and washing of the internal chambers - every 3-6 months, depending on the model and loading.
Do not overload the shelves with products beyond the norm. This creates extra load on the structure and can lead to deformation of the shelves, which begin to vibrate. Uniform distribution of products helps stabilize the temperature and reduce the frequency of motor starts.
Why is a new refrigerator noisier than an old one?
Modern refrigerators often seem noisier due to more powerful compressors and the presence of a No Frost system with fans. However, older units may simply have become deaf over time, or their noise may have become familiar to you. New models may have a different spectrum of noise frequencies that are perceived by the human ear as more irritating, even if the decibel level is technically lower.
Is it possible to lubricate a compressor if it hums?
No, the compressor in a domestic refrigerator is a sealed unit that is not intended for service at home. Inside it is a special oil mixed with freon. Any attempt to open or lubricate it will lead to depressurization and complete failure. If the compressor is humming due to mechanical wear, it needs to be replaced entirely.
Does the temperature in the room affect the noise of the refrigerator?
Yes, in a hot room the refrigerator has to work harder to maintain the set temperature. The compressor turns on more often and runs longer, which increases the overall background noise. In addition, at high ambient temperatures, the metal of the case expands more, which can increase cracking and clicking.
What to do if the refrigerator is in a niche and is humming?
Installing the refrigerator in a niche in a kitchen unit often creates a resonating effect. Make sure that all ventilation gaps specified in the instructions are observed (usually on the sides and top). If space allows, cover the walls of the niche with sound-absorbing material or make sure that the refrigerator does not touch the walls of the cabinet.