Sudden noise from the refrigerator can ruin anyone’s life, especially if the unit is located in the kitchen-living room or in a small room apartment where the walls are thin. Loud operation household appliances often become the first sign of an incipient malfunction, ignoring which can lead to expensive repairs or complete replacement of equipment. However, buzzing does not always mean a breakdown: sometimes it’s enough just to install the housing correctly or defrost the camera.
In this article we will analyze in detail the mechanics of sound occurrence, explain why compressor starts to work with an increased noise level, and will help you determine when you can cope on your own, and when you need to call a specialist. Understanding the nature of the sound is the key to quickly diagnosing the problem.
Before you panic, you need to listen carefully to the nature of the sound. It can be a monotonous hum, an intermittent crackling sound, a ringing knock or a whistle. Each of these sounds indicates different components of the unit. If the sound is accompanied by a sharp increase in temperature in the chambers, the device cannot be operated - this can lead to damage to the products.
Normal noise level and design features
Modern refrigerators, especially models with the system No Frost, emit more sounds than their drip-system predecessors. This is due to the presence of additional fans and more powerful motors. Manufacturers indicate the noise level in the technical data sheet, and a value of up to 40 dB is considered normal for kitchen appliances. If your device operates within these parameters, there is nothing to worry about.
It is important to distinguish between operating hum and abnormal sounds. Operating noise usually uniform, low-frequency and not irritating to the ear. It occurs when the compressor is turned on and off, as well as during operation of the blower fans. In models with an inverter motor, the sound can change smoothly, without sudden jumps in volume.
⚠️ Attention: If the refrigerator began to make noise immediately after purchase, louder than indicated in the passport, check the documentation. Perhaps the declared noise level was underestimated by the manufacturer, or you purchased a model without a quiet running system.
It is also worth considering the acoustics of the room. In an empty kitchen with tiled floors and walls, the sound can resonate, creating the illusion of a very loud operation. The presence of furniture, curtains and rugs can significantly reduce the perceived volume.
New refrigerants used in modern models can also circulate through the tubes with a characteristic gurgle or hiss, which is an absolutely normal physical process. These sounds should not be confused with a freon leak, which is usually accompanied by a complete lack of cold.
Problems with installation and vibration of the case
One of the most common reasons why a refrigerator hums loudly is improper installation. If the case is skewed or touches walls and furniture, vibration from the operating compressor is transmitted to surrounding objects, increasing significantly. Vibration is the main enemy of quiet operation of household appliances.
Check the horizontal installation using a building level. Even a slight misalignment can cause the door to not fit tightly and the compressor to work overload, producing louder sounds. Adjusting the legs allows you to set the unit perfectly level.
Also make sure that there is a gap between the back wall of the refrigerator and the wall of the room. Usually, at least 5-10 cm is required for normal air circulation. If the gap is smaller, the motor overheats and runs louder.
☑️ Checking the installation of the refrigerator
Often the source of rattling is objects standing on the top lid of the refrigerator. Microwave ovens, cereal cans, or decorative items may resonate with the frequency of the motor. Remove all excess from the surface of the case and check whether the extraneous sound has disappeared.
Faults of the compressor and start relay
The compressor is the heart of the refrigerator, and it is it that creates the main noise. If you hear a loud knocking, clanging or humming noise that gets worse over time, the problem is most likely in this unit. Wear of the engine shaft bearings leads to a metallic grinding noise.
Another common culprit is starting relay. This small element is responsible for starting the engine. If the relay contacts are burnt or the mechanism is jammed, the compressor may hum but not start, or make loud clicking noises when trying to start. In such cases, the thermal protection is often triggered and the unit turns off.
In older models with open compressors, the noise could be caused by loosening of the motor mounting bolts. Over time, vibration loosens the fastenings, and the engine begins to “walk” inside the casing, hitting the walls. In modern models, compressors are often covered with a plastic casing, but the principle remains the same.
⚠️ Attention: If the compressor runs continuously without turning off, and at the same time gets very hot (more than 60-70 degrees), immediately unplug the device. This can lead to a fire or combustion of the engine windings.
Replacing a compressor is a complex technical process that requires special equipment for evacuation of the system and charging with freon. It is impossible to perform this operation independently without skills and tools.
Fan noise in the No Frost system
Refrigerators with the system No Frost are equipped with fans that circulate cold air. Over time, dust gets into the fan bearings or the lubricant dries out, which leads to an unpleasant hum, howling or crackling sound. The sound may appear and disappear.
Fan noise often increases if ice builds up on its blades. This occurs when the door seal is broken or the defrost sensors are faulty. Ice chips get into the mechanism, causing beating and loud cracking. In such cases, complete defrosting of the unit is required.
How to distinguish fan noise from compressor noise?
Fan noise is usually higher, whistling or crackling. It may depend on whether the refrigerator door is open (in many models, the fan stops when the door is opened). The compressor hum is lower and more constant.
In two-chamber models there may be two fans: one in the freezer compartment, the other in the refrigerator compartment. Sound localization helps determine which node requires attention. If the sound comes from the top of the freezer, the problem is there, if from the freshness zone, then it’s in the top fan.
To replace the fan, you often have to disassemble the inner panel of the freezer. This requires caution, as plastic latches can be fragile, especially on older models.
Extraordinary sounds: gurgling, clicking and crackling
Not all sounds indicate a breakdown. Gurgling and overflow is a normal phenomenon caused by the movement of refrigerant through the evaporator and condenser tubes. This is especially often heard immediately after the compressor is turned off, when the pressure in the system is equalized.
Clicks can be caused by thermal expansion of materials. Plastic and metal contract and expand when temperature changes, producing characteristic sounds. This is especially true for new refrigerators or after a long defrost.
However, if the clicks are loud and frequent, this may indicate a malfunction of the thermostat or electrical problems. A cracking sound, reminiscent of the sound of breaking glass, is sometimes produced by ice bursting due to temperature changes in the water drainage system.
| Type of sound | Probable cause | Degree of danger | Necessary actions |
|---|---|---|---|
| Monotonous hum | Compressor operation | Normal | Observation |
| Loud knocking/clanging | Wear compressor | High | Call the technician |
| Whistling/howling | Fan or leakage | Medium | Checking rotation |
| Gurgling | Freon movement | Normal | Not required |
| Frequent clicks | Relay or thermostat | Average | Electrical diagnostics |
It is important to learn how to filter background noise. If the sound does not change for a long time and is not accompanied by other symptoms (heating, lack of cold), most likely this is a design feature of your model.
When you need to call a technician and diagnose
There are a number of signs in which self-repair is not only useless, but also dangerous. If you notice that the refrigerator is louder than usual and at the same time doesn't freeze or freezes poorly, this is a clear sign of a serious malfunction. This could be a freon leak or a blockage in the capillary system.
If the compressor hums, but does not start, and after a while there is a click and the hum stops, this is a sign of a malfunction of the starting relay or the motor itself. Operation in this mode will quickly destroy the compressor completely.
Professional diagnostics include checking the pressure in the system, the integrity of the motor windings and tightness contour. The technician uses a pressure gauge manifold and a leak detector, which allows him to accurately determine the cause of the noise.
⚠️ Attention: Under no circumstances attempt to open a sealed circuit or solder pipes on your own without the appropriate equipment and knowledge. This can lead to injury and permanent failure of the unit.
Regular maintenance, including cleaning the condenser from dust and checking the seals, helps extend the life of the equipment and maintain low noise levels.
Why is a new refrigerator loud?
New refrigerators may be louder due to undeveloped compressor parts (break-in period), a more powerful motor compared to the old model, or installation features. Let the equipment work for several days without load so that the lubricant is distributed among the components.
Is it possible to reduce the noise of an old refrigerator?
Yes, if the reason is vibration. You can place anti-vibration rubber pads under the legs, check the compressor fasteners (if there is access) and move the unit away from the wall. If the compressor is noisy, only replacing or soundproofing the box will help (which will worsen the cooling).
Is it dangerous if the refrigerator starts making noise at night?
At night, extraneous sounds are more audible due to the silence in the house. If the nature of the noise has not changed, it is not dangerous. If a new sound appears (knocking, grinding), it is better to listen during the day. Night power surges can also affect the operation of the motor, try turning on the stabilizer.
How does filling the chambers affect noise?
An empty refrigerator can operate louder due to acoustic resonance inside the chambers. Products absorb sound waves. However, overloading the chambers prevents air circulation, forcing the compressor to work longer and harder, which also increases the noise level.