A constant low-frequency hum coming from the kitchen can cause out of balance even of the calmest person. If your refrigerator started to make unusually loud sounds or the nature of the hum has changed, you cannot ignore it. Often the problem lies in a banal violation of installation rules, but in some cases this is a signal of a serious breakdown of the internal components.
Before calling a technician, it is worth carrying out an initial diagnosis yourself. Many causes of noise can be eliminated in a few minutes without special tools. In this article, we will take a detailed look at the mechanics of sound occurrence, methods for localizing them, and step-by-step instructions for restoring silence in your home.
Modern household appliances, be it Indesit, LG or Bosch, are designed to operate as silently as possible. However, the physical processes occurring inside the unit inevitably create vibrations. Understanding exactly how your unit operates will help you distinguish a normal operating sound from a dangerous hum.
The main causes of hum and vibration
The fundamental cause of any noise is vibration. The compressor, which is the heart of the refrigeration system, performs reciprocating piston movements during operation. This creates pulsation, which is transmitted to the body and surrounding objects. If the device is installed unevenly, this vibration increases many times over.
The second common reason is resonance. The design of the refrigerator has many parts: tubes, radiator grilles, plastic panels. If the fastening of one of these parts is loose, it begins to rattle in time with the operation of the motor. This is especially common in models with a system No Frostwhere fans are added.
It is also worth considering the age of the equipment. Over time, the lubricant in the moving parts of the compressor dries out, and the tubes lose their elasticity. Old refrigerantcirculating through the system can create a characteristic gurgling sound, which is often confused with the hum of a motor. It is important to learn to distinguish between these acoustic nuances.
Installation diagnostics: alignment and stability
The first thing you need to check is the geometry of the installation. Even the slightest tilt of the casing forces a heavy compressor to work with increased load, transmitting vibration to the floor. Take a building level and check the horizontal position of the refrigerator.
Often the problem is solved by simply adjusting the support legs. They can be twisted or unscrewed to compensate for uneven floor coverings. Make sure that all four support points fit tightly to the floor and do not wobble.
Pay attention to the distance from walls and furniture. If refrigerator stands close to cabinets or a wall, vibration is transmitted to them, and they begin to hum like resonators. It is necessary to provide a gap of at least 5-7 centimeters on all sides for free air circulation and vibration damping.
Checking the compressor and its mountings
The compressor is the main source of noise. Modern models use inverter motors, which are quieter, but can also hum when faulty. If the hum is accompanied by strong vibration of the body, the problem may be in the shock absorbers on which the motor is mounted.
Rubber cushions dry out over time and lose their properties. In this case, the metal housing of the compressor begins to contact the frame, creating a metallic clanging and hum. Replacing these gaskets is a task for an experienced technician, as it requires partial disassembly of the rear panel.
Also check the condition of the start relay. If it is faulty, the compressor may hum but not start, or make a loud clicking noise before starting. This is a critical moment that requires immediate intervention, as the motor may burn out.
| Sound type | Probable cause | Difficulty of eliminating |
|---|---|---|
| Low hum | Uneven installation, resonance floor | Low |
| Metal rattling | Touching of tubes, loosening of fasteners | Medium |
| Loud hum without cold | Faulty compressor or relay | High |
| Whistling or howling | Problems with the fan (No Frost) | Medium |
Fans and system No Frost
In refrigerators with a system No Frost fans are responsible for air circulation. Over time, ice can build up on the blades, throwing off balance and causing a hum. Dust can also get into the fan bearings, causing a characteristic howling sound.
If you hear a noise that comes and goes, most likely it is the fan. It turns on periodically at the command of the thermostat. To check this, open the refrigerator or freezer door. In most models, when the door is opened, the fan stops and the noise should disappear.
Fixing the problem often requires defrosting. Leave the refrigerator turned off for 10-12 hours. If after switching on the hum disappeared, then the reason was ice freezing on the blades. If the sound returns after a few days, the fan will need to be replaced.
Can the fan be lubricated?
Theoretically, you can put a drop of machine oil into the bearing by removing the protective sticker. However, this is a temporary measure. In a month, the noise will return, since the factory lubricant has already exhausted its life.
Foreign objects and resonance of parts
Sometimes the source of noise is outside. Check whether other objects are touching the refrigerator wall: curtains, towels, nearby bottles or cans. Even a light touch can turn the quiet operation of the motor into an obsessive hum.
Look inside the cameras. Shelves can rattle if they are not tightly inserted into the grooves. Glass shelves begin to vibrate when the compressor vibrates. Take them out, wipe them clean and put them back in as far as they will go. Also check the egg trays and containers on the door.
Pay special attention to the back wall. The condenser grille is located there. If it is deformed and touches the metal housing or tubes, ringing will occur. Carefully, trying not to damage the tubes, bend the grille or place a piece of foam rubber between it and the body.
⚠️ Attention: Never use sharp objects to bend the condenser tubes on the back wall. Damage to the tube will lead to an immediate release of refrigerant and expensive repairs, which are often not economically feasible.
When you need to call a specialist
There are situations when independent repair is impossible or dangerous. If the hum is accompanied by a lack of cold, and the engine runs continuously without turning off, this is a sign of a freon leak or blockage of the capillary system.
Another alarming symptom is a change in the color of the oil or the appearance of a burning smell. This indicates the compressor is overheating. In such cases, further operation may lead to a fire or complete failure of the unit.
If you have checked all external factors, aligned the legs, removed the resonance, but refrigerator continues to hum so that it interferes with sleep, the problem lies inside. Diagnostics of internal components requires special equipment and skills.
☑️ Checklist before calling a technician
Noise prevention and proper care
In order for equipment to serve for a long time and quietly, it is important to follow the operating rules. Regularly, at least once a year, completely defrost the refrigerator, even if you have a system No Frost. This will help prevent ice from fouling internal mechanisms.
Wipe the rubber door seals and lubricate them with special silicone grease. This will prevent them from drying out and whistling when closing. Also keep an eye on the cleanliness of the condenser at the back - a layer of dust impairs heat transfer, causing the motor to work harder and noisier.
Do not overload the shelves with excessively heavy objects. The additional weight increases the overall vibration of the structure. Distribute the food evenly so as not to create distortions, which can lead to deformation of the case over time.
Why does a new refrigerator hum louder than the old one?
Modern models often use more powerful compressors and environmentally friendly refrigerants that can operate under high pressure. In addition, the thin walls of the new buildings dampen sound worse than massive Soviet units. This is often normal and only requires a period of “grinding in” of the parts.
Can an empty refrigerator hum?
Yes, an empty refrigerator can hum more strongly, since food acts as an additional acoustic buffer and thermal mass. When first starting up or after defrosting, an empty unit will work more intensely until it reaches temperature.
Does the temperature in the room affect noise?
Absolutely. In a hot room, the compressor is forced to work longer and more often to maintain the desired cold. This increases the total operating time and, accordingly, the time during which you hear its humming.