The purchase of new household appliances is always accompanied by the expectation of perfect operation, but in reality, the first use often causes bewilderment and even anxiety among the owners. Instead of silence or a barely audible whisper, the unit can produce loud, frightening sounds, which, in the user’s opinion, should not be characteristic of an expensive modern device. The noise of a new refrigerator is one of the most common reasons for contacting service centers, although in most cases the equipment is absolutely working.
Modern models, especially those running on inverter compressors or using new generation refrigerants, have their own unique acoustic signature, different from old Soviet units. Understanding the physics of the processes occurring inside the system will help you distinguish normal operation from a real malfunction and avoid wasting time on calling a technician.
In this article we will analyze in detail the mechanical, physical and installation causes of extraneous sounds, and also determine the limits of the permissible noise level in accordance with technical regulations.
Physics of compressor and refrigerant operation
The main source of sound in any refrigerator is the compressor, which is an electric motor that pumps up pressure in the system. In new models, even if they are equipped with modern ones, the gas compression process cannot be absolutely silent. When first started, the compressor operates at maximum power in order to cool the entire volume of the chamber to the specified temperature values, which is inevitably accompanied by a more intense hum. inverter motors, the gas compression process cannot be absolutely silent. When first started, the compressor operates at maximum power in order to cool the entire volume of the chamber to the specified temperature values, which is inevitably accompanied by a more intense hum.
In addition to the mechanical hum of the motor, a significant part of the background sound is created by the movement of the refrigerant through the tubes of the evaporator and condenser. Liquid freon, turning into a gaseous state and back, makes characteristic sounds that may resemble gurgling, pouring water, or even a slight hiss. These acoustic effects are especially audible in new refrigerators, since the system has not yet been fully filled with an oil film, and the tubes vibrate due to sudden changes in pressure.
⚠️ Attention: If the sound resembles a metallic clang, grinding or sharp knock of the piston on the cylinder walls, this may indicate mechanical damage to the compressor during transportation. In this case, operation of the device is prohibited.
It is important to consider that the noise level directly depends on the type of refrigerant and the design of the heat removal system. For example, models with a No Frost system will always make noise louder than their drip counterparts due to the constant operation of the fans. It is also worth noting that in the first 24–48 hours of operation, the refrigerator may behave more “loudly”, as all moving elements grind in and the pressure in the circuit stabilizes.
Why are old refrigerators quieter than new ones?
Old models often seem quieter due to a thicker layer of insulation and less powerful, but inertial compressors. Modern units are more powerful, more compact and require more active heat exchange, which creates more acoustic noise, although their energy efficiency is much higher.
Noise level standards for household appliances
To objectively assess the situation, it is necessary to rely not on subjective sensations, but on technical standards. According to current GOSTs and international standards, the noise level of household refrigerators should not exceed certain values, which are usually indicated in the product data sheet. For most modern models, a value in the range from 35 to 45 dB is considered normal.
However, human perception of sound is subjective and depends on the frequency characteristics of the noise. A low-frequency compressor hum may be less annoying than a high-frequency whistling or crackling sound, even if the decibel volume is the same. Newer refrigerators often have a wider frequency range due to the complex air circulation system.
The following table helps classify sound levels and their effect on comfort:
| Sound Level (dB) | Source Characteristics | Perception person | Status for the refrigerator |
|---|---|---|---|
| 25–30 dB | Whisper, ticking clock | Barely audible, comfortable | Perfect silence (rarely) |
| 35–40 dB | Quiet conversation, rustling pages | Background, does not interfere | The norm for new models |
| 45–50 dB | Average conversation volume | Noticeable, but tolerable | Permissible maximum |
| 55+ dB | Loud speech, printer operation | Annoying, interferes with rest | Requires verification |
It is worth remembering that measurements by the manufacturer are often carried out in special acoustic chambers, so in an ordinary kitchen with its resonant surfaces (tiles, glass, empty shelves), the sound may seem louder. If your new unit makes sounds in the range of 40–42 dB, it is within technical regulations.
The influence of transportation and installation on acoustics
One of the most common reasons why a new refrigerator makes more noise than expected is improper transportation or poor-quality installation. Even if the housing is externally intact, the internal suspension of the compressor could receive microtrauma if the unit was transported lying down without maintaining an angle of inclination or was abruptly placed on the floor.
A critically important step is leveling the device. If the refrigerator is not level, a misalignment occurs, which leads to an uneven load on the compressor supports and a change in the geometry of the housing. This causes resonant vibrations that enhance any, even standard, sound of the engine. Adjusting the legs is the first thing you need to do after unpacking.
☑️ Correct installation of the refrigerator
Also, do not forget about transportation materials. Factory retaining elements, gaskets or pieces of foam may remain inside the compressor and on its casing, which begin to knock when vibrating. In some cases, the compressor itself is mounted on shipping bolts, which required need to be unscrewed before turning it on, otherwise the vibration will be transmitted to the entire case.
⚠️ Attention: If the refrigerator was transported in a horizontal position, it cannot be turned on immediately. The oil needs time (from 2 to 24 hours) to drain into the compressor crankcase. Switching on “dry” can lead to jamming of the piston group and the appearance of an irreparable metallic knock.
Features of the No Frost system
Owners of models with an automatic defrosting system No Frost often encounter new sounds that were not present in the old ones "crying" refrigerators. The main source of noise here is the fan, which circulates cold air through the chambers. Its operation may be accompanied by a uniform hum or whistle, depending on the speed of rotation of the blades.
In addition, the system No Frost implies periodic switching on of the heating element to defrost the evaporator. This process is often accompanied by crackling, clicking, or the sound of ice breaking. This is due to thermal expansion and contraction of the plastic parts of the air ducts and the evaporator itself. For a new device, such sounds may seem alarmingly loud, but they are a completely normal physical process.
Sometimes users hear the sound of objects falling inside the camera. This may be frost or small pieces of ice that fall off the air duct damper when switching the damper operating modes. In new refrigerators, plastic elements have not yet “got used to it”, so the sounds of their movement (clicks of the damper servomotor) may be louder.
Resonance phenomena and interaction with furniture
Often the source of the problem is not the refrigerator itself, but its interaction with the surrounding space. A new unit full of products has a large mass, but when the compressor operates, high-frequency microvibrations occur. If the refrigerator body touches the wall of a kitchen unit, a shelf with dishes or other equipment, these vibrations are transmitted to them, causing rattling.
Particular attention should be paid to the internal components. Glass shelves, bottles placed close together, or containers on the door that are poorly secured can resonate with the frequency of the compressor. In new refrigerators, the shelf seals are still rigid and do not dampen vibration as effectively as in devices that have been in use for several years.
To diagnose resonance, you can conduct a simple experiment: at the moment an extraneous sound appears, gently press the side wall of the refrigerator or the shelf inside with your hand. If the sound disappears or changes, then the cause is found in resonance. In this case, it is necessary to move the equipment slightly away from the furniture or overload the products by changing their position.
When it is necessary to contact the service center
Despite the fact While many sounds are normal, there are signs that cannot be ignored. If the new refrigerator makes sounds that can be described as emergency, you should stop using it and call a technician. These signs include: constant loud knocking, similar to hammer blows; a shrill whistle that gets stronger over time; or a burning smell combined with unusual noise.
Also a cause for concern is the situation when the refrigerator makes noise continuously without turning off for rest. The normal operating cycle involves periodic pauses (or a decrease in speed in inverter models). If the engine hums 24 hours a day with the same intensity, this may indicate a freon leak or a thermostat malfunction, which requires professional diagnostics.
It is important to distinguish between warranty and non-warranty cases. Factory defects of the compressor or assembly problems identified in the first days are usually corrected free of charge. However, if it turns out that the noise is caused by improper transportation (for example, turning on immediately after horizontal transportation), the service may refuse free repair.
⚠️ Attention: Specifications, types of refrigerants and design features may vary from manufacturer to manufacturer. Before calling for service, be sure to check the "Possible malfunctions" section in the official user manual for your specific model, as brand-specific sounds may be listed there.
Is it normal for a new refrigerator to crack when it cools?
Yes, this is absolutely normal. The cracking occurs due to thermal expansion and contraction of the materials (plastic, metal) from which the inner box and the evaporator are made. This is especially true for new devices until the materials have gone through several heating and cooling cycles. The sound may be similar to the crackling of a fire or clicks.
Why does the refrigerator hum only at night?
During the day, the background noise of the street, TV and conversations masks the operation of the equipment. At night, in silence, even the standard hum of the compressor (35–40 dB) becomes clearly audible. In addition, at night, the voltage in the electrical network can stabilize, which allows the compressor to operate in a more powerful mode, if it is a smart model.
Is it possible to reduce the noise of a refrigerator with your own hands?
You can try installing the unit on anti-vibration pads under the legs, check whether the pipes at the back are touching each other or the cabinet wall, and also make sure that there is nothing inside rattles. It is almost impossible to radically reduce the noise of a standard compressor without losing the warranty.
Do inverter refrigerators make a lot of noise?
Inverter models are usually quieter than classic ones, since they do not have sudden starts and stops. They operate continuously at low speeds, creating a monotonous, low-frequency background that the human ear perceives less keenly than the intermittent hum of the old type.
What should you do if the refrigerator gurgles constantly?
A constant gurgling sound may indicate that the refrigerator is overloaded with food and the air is not circulating normally, or that the device is not level. level. If gurgling is accompanied by insufficient cooling, there may be an air lock in the system or there is a leak, which requires calling a technician.