A sudden hum or increasing noise in kitchen appliances can unsettle any owner. If your the refrigerator began to make a lot of noise, this is the first signal that changes have occurred in the operation of the unit that require attention. Ignoring extraneous sounds often leads to more serious damage, when simple adjustment no longer helps.
However, there is no need to panic ahead of time. Loud operation does not always mean a critical malfunction of internal components. Sometimes the reason lies in a simple incorrect installation or temporary overload of the motor. In this article, we will analyze in detail the mechanics of the occurrence of sounds and help determine whether the noise is a sign of a breakdown.
Modern models of household appliances, whether Indesit, Beko or premium Liebherrwork on similar physical principles. Understanding these processes will allow you to quickly diagnose the problem. We will consider both external factors and internal malfunctions that require specialist intervention.
Is normal operating noise or a malfunction signal?
The first thing to do is to draw the line between normal operation and an anomaly. Any refrigeration unit makes sounds during operation. The circulation of refrigerant through the pipes, the periodic switching on of the compressor and the operation of the defrost system - all this is accompanied by an acoustic background. Usually this is a quiet hum or periodic gurgling.
Sudden changes in the sound picture should alert you. If a previously quiet device suddenly hummed like a tractor, or a piercing whistle appeared, it means that the balance of the mechanisms is disturbed. The critical threshold is considered to be a noise level above 40 dBwhich is comparable to a loud conversation in a quiet room.
It is important to take into account the age of the equipment. Old Soviet models like the ZIL or Morozko are initially louder than their modern counterparts due to the design features of the motors and the lack of noise-absorbing materials. New models with inverter compressors, such as Samsung Digital Inverter, should operate almost silently.
There is a simple test: place your hand on the case. If you feel a strong, rhythmic vibration that is transmitted to the walls or floor, then the problem is not only in sound, but also in the mechanical transmission of vibrations. This often indicates that vibration is not damped correctly.
Installation problems: geometry and vibration
The most common reason why the refrigerator began to make a lot of noiseis not due to failure, but due to incorrect positioning. The body must be perfectly level. If one of the legs does not touch the floor or, on the contrary, presses harder than the others, a misalignment occurs. This leads to the operating compressor shaking the entire housing.
Check the distance to the walls and furniture. For normal air circulation and the absence of resonance, a gap of at least 5-10 cm is required. If the unit is moved close to the wall, the sound wave is reflected and amplified, creating an echo effect. Also, the tubes at the back should not touch the wall, otherwise vibration will be transmitted to building structures.
⚠️ Attention: When moving the refrigerator, never tilt it more than 40 degrees. Oil from the compressor can enter the refrigerant circuit, which will cause water hammer and loud knocking when first started.
Often the source of rattling is objects located inside or outside. Check if the bottle has fallen on the shelf or if the dishes on the door are vibrating. Even a small spoon left on the top panel can create an annoying noise from the motor.
Make sure that the adjusting screws on the legs are screwed all the way to the floor. The plastic caps on the legs can wear off over time, causing the metal base to vibrate against the linoleum or tile. Placing a rubber mat under the device often solves the problem of hum.
To eliminate installation problems, use the following algorithm of actions:
- 📏 Check the horizontalness of the case with a building level in two planes.
- 🔧 Tighten the front legs so that the doors close on their own easily push.
- 🧱 Move the appliance away from the wall at least 7-10 cm for free air circulation.
- 👐 Make sure that the back grill and tubes do not touch the walls, floor or cabinets.
Compressor malfunctions: the heart of the refrigerator
If everything is fine with the installation OK, attention switches to the main unit - the compressor. It is he who is responsible for compressing and pumping freon. When the refrigerator is humming he is constantly and very loud, most often the motor is to blame. Over time, the shaft bearings wear out, play appears, and a metallic knock becomes clearly audible.
A special case is problems with the start relay. This small element is responsible for starting the engine. If the relay is faulty, the compressor may attempt to start, make a loud clicking noise, hum for a few seconds, and then shut down. After some time, the cycle repeats. This condition is called “peddling” and quickly disables the motor.
Inverter compressors installed in models LG or Boschoperate differently. They do not turn off completely, but change power. If such a motor begins to make strange sounds, this may indicate problems with the electronic control unit or the motor windings. Diagnostics here requires special equipment.
It is important to distinguish the nature of the sound. A uniform hum is the engine running under load. An intermittent knocking or clanging sound is a sign of mechanical failure of the internal parts. If you hear that the motor is running without interruptions and does not turn off, and the noise is increasing, this is a sign of a freon leak: the motor is trying to compensate for the lack of cold by constant operation.
Fan and No Frost system
In refrigerators with a system No Frost fans are responsible for air circulation. There may be one or two of them: in the freezer and refrigerator compartments. If the refrigerator began to make a lot of noise and the sound resembles the hum of an airplane or the friction of plastic, the problem is most likely in them.
Over time, an ice crust grows on the fan blades and on the walls of the air ducts. The blades begin to touch this ice, producing a characteristic crackling or grinding sound. The grease in the fan bearing may also dry out, causing it to begin to hum when rotating.
In some models, for example, in older Indesit or Atlant, the fan is located in a niche behind the back wall of the freezer. It is difficult to get to and requires partial disassembly. If the fan is noisy, you can try to lubricate it, but most often a complete replacement of the unit is required.
Signs of a fan malfunction:
- ❄️ The noise intensifies when the door is opened (in some models, the fan, on the contrary, stops).
- 🌀 A whistle or howl is heard that changes tonality.
- 🧊 A “fur coat” of uneven shape has formed in the freezer.
- 🔇 The sound disappears if you manually stop the fan (carefully!).
Sometimes the noise is caused by a clogged drainage system. The water does not go away, it freezes in the form of ice, and the fan begins to grind this ice. Regular defrosting (at least once every six months) helps to avoid such situations.
Refrigerant and hydraulic sounds
Liquid refrigerant, moving through the pipes of the system, can make sounds reminiscent of gurgling, pouring water or hissing. In most cases this a normal physical process, especially immediately after turning the compressor on or off. Freon changes its state of aggregation, which causes acoustic effects.
However, if the gurgling becomes too loud, turns into a whistle, or is accompanied by a drop in cooling efficiency, this is an alarming symptom. There may be a gas leak or a clogged capillary tube. Air pockets form in the system, which interfere with normal circulation.
The table below will help classify sounds and their probable sources:
| Sound type | Probable cause | Urgency of repair |
|---|---|---|
| Uniform hum | Normal operation of the compressor | Not required |
| Gurgling, overflow | Movement of freon through the tubes | Not required |
| Crackling, grinding | The fan touches the ice | Medium (defrost) |
| Loud knocking, clanging | Compressor destruction | High |
| Whistling, hissing | Freon leak or breakdown | High |
It is worth noting that after transporting the refrigerator in a lying state, it needs time to adapt. The oil should drain into the compressor crankcase. If you turn on the device right away, it will work very loudly and may fail.
How long should you wait after transportation?
If the refrigerator was transported vertically, 2-3 hours of settling is enough. If in a horizontal position - at least 8-12 hours, and in winter even longer, so that the oil and glass warm up.
Rattling of structural elements
Sometimes the source of noise turns out to be trivially simple. During long-term use, the screws and bolts holding the casings and components together may become loose due to constant vibration. The metal casing on the rear wall that covers the compressor often becomes a resonator.
Check the tube fastenings. The copper tubes of the circuit must not touch each other or the housing. In the factory, they are fixed with plastic clips, which dry out or break over time. The tubes begin to vibrate and knock on the metal.
Also pay attention to the condensate collection tray, which is located above the compressor. If it is not installed tightly or is skewed, it will rattle when the motor is running. It is enough to correct it or place a piece of foam rubber.
Algorithm for searching for rattling:
- 🔍 Inspect the rear grille: is it securely fastened?
- 🖐️ Gently press various parts of the body with your hand while the engine is running. If the noise disappears, you have found the source.
- 🔩 Check the tightness of the compressor mounting bolts (access to the bottom of the unit is required).
- 📦 Remove all foreign objects from the top cover of the refrigerator.
⚠️ Attention: Before reaching with your hands to the back components and tubes, be sure to disconnect the refrigerator from the power supply! Being under voltage even with the motor turned off is dangerous.
☑️ Noise diagnostics
When to call a technician: critical situations
There are situations when self-repair is not only useless, but also dangerous. If the refrigerator began to make a lot of noise at the same time it stops freezing, or an oily puddle appears on the floor, call a specialist immediately. These are signs of depressurization of the circuit or breakdown of the compressor.
Continuous operation of the motor without turning off, combined with a strong hum, indicates that the system cannot gain temperature. This could be caused by a freon leak or a clog. Further operation in this mode will finish off the compressor, and repairs will become economically unfeasible.
If you hear the smell of burning or burning plastic along with a change in the sound of operation, this is a sign of overheating of the wiring or motor windings. In this case, the device must be immediately de-energized.
Remember that modern refrigerators are complex devices. An attempt to solder tubes on your own or replace a compressor without a vacuum sealer and pressure gauges is doomed to failure. You can lose the refrigerant and ruin the new motor in a few minutes.
Why does the refrigerator hum only at night?
At night, the overall noise level in the apartment decreases, and previously unnoticeable the buzzing becomes audible. In addition, at night the voltage in the electrical network may stabilize or, conversely, jump, which affects the operation of the motor. Also, other devices operate during the day, masking the sound of the refrigerator.
Is it possible to lubricate a compressor if it starts to hum?
Modern compressors are sealed units. They do not have holes for adding or changing oil. If the bearings are worn out or the oil has lost its properties, the compressor must only be completely replaced. Lubricating the outside will not have any effect.
Is it normal that a new refrigerator is louder than the old one?
Not always. Newer models are often quieter thanks to inverter technology. However, if you had an old quiet unit, and the new one turned out to be loud, perhaps this is a feature of a particular model or a defect. Study the product data sheet: it shows the standard noise level in dB.
How does noise affect the service life of the refrigerator?
Noise itself is a consequence, not a cause. But if the noise is caused by vibration, it gradually destroys the soldering of the tubes, fasteners and bearings. Therefore, eliminating the causes of strong noise directly prolongs the life of the appliance.