Extraneous sounds emanating from household appliances always cause concern to the owner, especially when it comes to expensive equipment that operates around the clock. The refrigerator makes a cracking sound is one of the most frequent complaints with which users contact service centers or search for information on the Internet. However, the characteristic crackling sound does not always indicate a critical malfunction that requires immediate intervention from a technician.
In most cases, these acoustic manifestations are associated with natural physical processes occurring inside the unit. The expansion and contraction of materials, the operation of the compressor, the movement of the refrigerant - all this creates an acoustic background. Understanding the nature of these sounds will allow you to distinguish the normal operation of the device from the real symptoms of a breakdown, which will help save time and money on unnecessary repairs.
In this article we will analyze in detail the mechanical and physical causes of cracking, consider the features of different cooling systems and determine in which cases it is necessary to sound the alarm. Modern models they can be quite noisy due to their design features, and it is important to know these nuances.
Natural physical processes and thermal expansion
The most common reason the refrigerator makes a cracking soundis the banal thermal expansion of materials. The internal chamber, shelves and body of the device are made of various materials: plastic, glass, metal and polymers. Each of them has its own coefficient of thermal expansion.
When the unit turns on or off, the temperature inside the chambers changes sharply. Plastic elements can shrink or expand faster than glass shelves or metal frames. At the points of their contact, tension arises, which is released in the form of a short, loud click or crack. This is an absolutely normal phenomenon, especially typical for new devices or after defrosting.
⚠️ Attention: If a cracking sound occurs once or at long intervals and is accompanied by a change in temperature, this is most likely a harmless physical process of adaptation of materials.
Often users notice that refrigerators with the No Frost system crackling more often. This is due to the presence of a large number of plastic air ducts and dampers, which are also subject to temperature fluctuations. The sounds may be similar to the cracking of wood or the bursting of bubbles.
No Frost defrost system operation
If your the refrigerator makes a cracking sound periodically, approximately every 8-12 hours, and the sound is coming from the back of the freezer, we may be talking about the automatic defrost system. In units with technology No Frost or Low Frost frost periodically builds up on the evaporator, which must be removed.
The defrost timer turns on the heating element (heating element), and the ice begins to quickly melt. A sharp change in temperature and the movement of melting water, as well as flying pieces of ice along drainage channels can create characteristic sounds. They range from gurgling to a distinct crackling and hissing.
- 🧊 Cyclicity: The sounds appear regularly at certain intervals.
- 💧 Localization: The noise comes from the depths of the freezer, where the evaporator is hidden.
- ⏱️ Duration: The process can last from several minutes to half an hour.
Sometimes a crash occurs due to the fact that an ice crust freezes on the fan blades. When the ice gets too thick, it can hit the rotating parts, causing a rhythmic knocking or cracking noise. In a working device, the defrost timer does not allow this, but if the system fails, the sounds will become constant.
Why does ice crack?
Ice, when heated by a heating element, changes its crystalline structure and cracks, just as ice cracks on a river in the spring. These sounds are transmitted through the body and may seem louder than they actually are.
Malfunctions of the compressor and start relay
The situation becomes more serious if the refrigerator makes a cracking sound at the moment you try to start the motor-compressor. The compressor is the heart of the unit, and any malfunctions in its operation require attention. Often a cracking sound is heard in the lower rear part of the device, where the motor is located.
One of the common causes is a malfunction of the start relay. This small element is responsible for starting the engine. If the relay has worn out or failed, it may make a loud clicking or cracking sound when you try to start the compressor. The motor hums, clicks, but does not start, after which another click is heard, and the process repeats after a while.
⚠️ Attention: Operating the refrigerator with a faulty start relay or a jammed compressor can lead to burnt out motor windings and expensive repairs.
Crackling noise may also occur the compressor itself, if there is mechanical damage to the internal valves or piston group. In this case, the sound will be metallic, hard and accompanied by strong vibration of the case. Inverter compressors, unlike conventional ones, they operate more smoothly, but if they break down they can also make uncharacteristic sounds.
Rattling of structural elements and fasteners
Sometimes the answer to the question why the refrigerator makes a cracking soundlies not in internal mechanics, but in poor fixation of external or internal elements. Vibration from a running compressor is transmitted to the entire housing, causing loose parts to resonate and knock against each other.
First of all, check the compressor fasteners. If the bolts holding the motor are loose, or if the rubber shock absorbers are worn, metal will bang against metal, creating a loud clanging and cracking sound. Also, the source of noise can be the tubes of the refrigeration circuit if they are located too close to the body or to each other.
☑️ Diagnostics of external noise
Do not forget about the internal fittings. Glass shelves, plastic containers for vegetables, bottles on the door - all of this can vibrate. It is enough to place an empty plastic container on the shelf so that it begins to rattle in time with the operation of the motor, creating the illusion of a breakdown of the unit itself.
The influence of incorrect installation on acoustics
Correct installation of household appliances is the key to their quiet operation. If the refrigerator makes a cracking soundthe rules for its installation may have been violated. Even a perfectly serviceable unit will make noise if it is installed skewed or without the necessary clearances.
When installing, it is important to level the device horizontally and vertically using the adjustable support legs. If the refrigerator is positioned crookedly, the load on the compressor is distributed unevenly, which increases vibration. In addition, misalignment can lead to a loose fit of the door, which causes additional bangs when it slams or spontaneously closes.
| Installation parameter | Normal | Consequences of violation |
|---|---|---|
| Gap at walls | Minimum 5-10 cm | Overheating, increased noise, cracking of plastic |
| Position of legs | Close contact with the floor | Vibration, hum, body rattling |
| Proximity to furniture | Lack of contact | Transfer of vibration to cabinets (resonance) |
| Level | Strictly horizontal | Incorrect operation of the oil in the compressor |
It is also important to consider the floor material. Vibration is transmitted better on hard laminate or tile than on linoleum or carpet. The use of anti-vibration footrests can significantly reduce noise levels and eliminate secondary noise from vibration of objects around.
When an urgent call to the technician is necessary
Despite the fact that many sounds are natural, there are situations when The refrigerator makes a cracking soundindicating a serious threat. Ignoring these signals can lead to spoilage of food and complex repairs.
The alarm should be sounded if the crackling sound is accompanied by a lack of cold. This is a sure sign that the compressor is trying to start but cannot, or the refrigerant has leaked from the system. It is also dangerous if the sounds become louder every day or change their character from a quiet crackling to a loud grinding.
- 🔥 The smell of burning: If the crackling is accompanied by the smell of burning wiring or plastic.
- 🌡️ Temperature rise: The chambers become warm, food spoils.
- ⚡ Power surges: The light in the refrigerator blinks or goes out in time with the clicks.
In such cases, independent repair is not recommended, as it requires special tools and knowledge. Professional diagnostics will accurately identify a failed unit and replace it, preserving the life of the rest of the equipment.
Can a crackling sound be a sign of a freon leak?
Crackling itself rarely indicates a leak. However, if the leak occurred due to mechanical damage (for example, a tube was broken during defrosting), the nature of the compressor operation could change, which causes knocking. But more often the leak passes silently, and the only sign is the absence of cold.
Why does the new refrigerator crack more than the old one?
New materials have not yet “got used to it.” In the first weeks of operation, plastic actively reacts to temperature changes. In addition, modern models often have more powerful compressors and a complex ventilation system, which can create more noise than in old Soviet units.
Does the amount of food in the refrigerator affect crackling?
Yes, indirectly. A full refrigerator holds the temperature better, and the compressor turns on less often, which means there is less thermal expansion. An empty unit heats up faster, the motor runs more often, and expansion-compression cycles are repeated more actively.