A sudden extraneous sound in kitchen appliances often becomes a cause for serious concern. Crackling in the refrigerator is one of the most common types of acoustic signals faced by owners of household appliances technology. In most cases, these sounds do not pose a threat to the functionality of the unit, however, they should not be ignored completely, since the nature of the noise can change depending on the condition of the internal components.
To understand the nature of the cracking, it is necessary to take into account the physical design of the device. The housing, evaporator and other elements are constantly exposed to temperature changes, which leads to changes in their volume. Thermoregulator and the defrosting system also contribute to the overall acoustic background. Understanding whether the sound is normal or a symptom will help you avoid unnecessary expenses on calling a technician or, conversely, prevent serious damage.
In this article we will analyze in detail all possible causes, from natural physical processes to technical malfunctions. You will learn to distinguish between the safe crackling of plastic and the alarm signals of mechanical components, and also find out in which situations immediate intervention is required.
Natural physical processes: expansion and contraction of materials
The most common reason for the sound of noise crackling in the refrigeratorlies in the laws of physics. The inner walls of the chamber, plastic shelves and metal evaporator are made of materials with different coefficients of thermal expansion. When the compressor is running, the temperature inside drops and the materials are compressed. When the motor stops, heating and expansion occur, which is often accompanied by characteristic clicks or crackling sounds.
This effect is especially noticeable in new models or after defrosting. Plastic that has not yet gone through a full shrink cycle may react more loudly to temperature changes. Also, the sounds may intensify if you have just loaded a large amount of warm food into the chamber, causing a sharp change in the thermal balance.
⚠️ Attention: If the crackling sounds rhythmically and coincides with the moments when the motor is turned on or off, most likely it is simply the plastic of the case or trays that is “breathing.”
It is important to note that that in systems with No Frost the processes of expansion and contraction occur more intensely due to the constant circulation of air and the operation of fans. Thin walls of plastic air ducts can react to the flow of cold air with a characteristic crackling sound, which is an absolutely normal operating condition.
Why does a new refrigerator crack louder than the old one?
In new appliances, the materials have not yet completed full heating and cooling cycles, so their deformation occurs more sharply when the temperature changes. Over time, after several months of operation, the plastic “gets used” to the operating modes, and the number of sounds usually decreases.
Operation of the automatic defrosting system
Modern refrigerators are equipped with an automatic defrosting system, which periodically removes ice from the evaporator. During this work, specific noise may occur. When the heating element turns on, the ice begins to melt and water flows into the drain pan. Dripping water and bursting air bubbles in melting ice can create sounds similar to faint crackling or hissing.
In addition, louder clicking sounds may be heard when switching from cooling to defrosting mode (and vice versa). This works thermal relay or valves that switch refrigerant flows in some models. The sound can be quite sharp, but it lasts only a fraction of a second.
- 🧊 Ice melting: Burst of air bubbles inside the ice crust when heated.
- 💧 Water drain: The sound of moisture dripping into the drainage system, especially if it clogged.
- ⚙️ Switching modes: Click of the thermostat or start relay in the defrost cycle.
If your refrigerator operates according to the system No Frostthen during defrosting the fan stops, and the heating element heats the evaporator. A sharp temperature change on the metal tubes of the evaporator also causes their deformation and a corresponding sound background. Typically this process takes from 15 to 30 minutes and is repeated every 8-12 hours of operation.
Deformation of plastic elements and trays
Often the source of the irritating crackling sound is not metal components, but plastic elements of the interior decoration. Shelves, crisper drawers, door baskets and decorative panels shrink as they cool. If an element is pressed tightly against the wall or sandwiched between other parts, when changing sizes, friction occurs, which we hear as a creaking or crackling sound.
Door shelves are especially susceptible to this phenomenon. When you open the door, warm air hits the plastic, it quickly heats up and expands. When closed, it cools down again. This cycle may cause periodic clicking sounds. It is also worth checking to see if any drawers are warped, which could touch the chamber wall when vibrating.
To diagnose this problem, try gently pressing your hand on different plastic parts when the sound occurs. If the cracking stops or, on the contrary, is provoked by pressing, then the problem is precisely the mechanical friction of the plastic. In this case, it is recommended:
- 🔍 Inspect the tight fit of all removable elements.
- 🧴 Lubricate the rubbing surfaces with silicone grease (food safe).
- 🔄 Change the position of the shelf or drawer to eliminate tension.
Sometimes a cracking sound occurs due to the fact that food in bags touches the back wall of the refrigerator. When cooled, the package contracts or freezes, creating tension that breaks with a characteristic sound. Make sure there is a small gap between the products and the back wall.
Problems with the compressor and start relay
The situation becomes more serious if the crackling noise comes directly from the compressor motor located at the lower rear of the unit. Normally, a working compressor hums, but does not crackle. The appearance of a crackling sound in this area may indicate mechanical wear of internal parts or electrical problems.
One of the common causes is a malfunction start relay. This device is responsible for starting the engine. If the contacts inside the relay are burnt or the mechanism is stuck, when you try to start, a distinct crackling or clicking sound is heard, after which the compressor may hum, but not start, or turn off immediately.
⚠️ Attention: If you hear a crackling sound from the compressor area, and the refrigerator has stopped freezing or turns on only for a few seconds, immediately disconnect the appliance from network.
Another reason is the entry of a foreign object or loosening of the fastening bolts of the compressor itself. The vibration of a running motor is transmitted to the casing, and if it is poorly secured or touches the pipe, rattling occurs, turning into a crackling sound. Copper tubes of the refrigerant circulation system can also crack if they are located too close to each other.
The influence of refrigerant and pressure in the system
The refrigerant (freon) circulating through the tubes is under pressure and constantly changes its state of aggregation from liquid to gaseous. As the liquid moves through narrow capillary tubes and expands in the evaporator, it may produce sounds resembling gurgling or a low hiss. However, in some cases this may be perceived as crackling.
If a microcrack or leakage has formed in the system, the refrigerant may leak out. The process of leaking gas under pressure is sometimes accompanied by a whistle or frequent crackling sound. This is a dangerous situation, since without freon, the refrigerator will stop cooling, and the compressor may burn out from overload.
It is difficult to diagnose a leak on your own, but there are indirect signs:
- 🌡️ The temperature in the chambers does not drop to the specified values.
- 🔊 The sound becomes constant and does not depend on the operating cycle.
- 👀 There may be oily stains (oil from the compressor) on the back wall or floor under the refrigerator.
It is important to distinguish between normal freon bubbling after stopping the compressor (this is residual movement in the tubes) and pathological crackling. The normal sound subsides a few minutes after the engine is turned off.
Diagnostics: when you need a technician, and when you can relax
In order not to waste money on calling a specialist unnecessarily, carry out an initial diagnosis. Assess the nature of the sound, its frequency and accompanying symptoms. Below is a table that will help classify the problem.
| Symptom | Probable cause | Is repair needed? | Urgency |
|---|---|---|---|
| Rare clicks when on/off | Thermal relay, expansion of plastic | No | Not required |
| Crackling inside the chamber, changes when you press the shelves | Deformation of the plastic, trays | No (adjustment) | Low |
| Loud crackling from behind, the refrigerator does not freeze | Start relay, compressor | Yes | High |
| Constant hissing and crackling, there is an oil smell | Freon leakage | Yes | Medium |
| Crackling only during defrosting (No Frost) | Ice melting, heating element operation | No | Not required |
If you determine that the problem lies in the mechanical part (compressor, relay), self-repair is only possible if you have the appropriate skills and tools. Otherwise, it is better to contact a service center. Remember that interfering with the refrigerant circulation system requires a license and special equipment.
☑️ Initial check of the refrigerator
Prevention and operating rules
To minimize the risk of extraneous noise and extend the life of the appliance, follow simple operating rules. Proper installation of the refrigerator is the first step towards silence. Make sure that the appliance is level and its feet are firmly planted on the floor. Vibration is the main provocateur of the displacement of parts and the occurrence of friction.
Do not load hot foods into the refrigerator. A sharp jump in temperature causes all elements to compress faster and more unevenly, which increases the load on plastic and metal. Also, do not overcrowd the chamber: air gaps are necessary for normal cold circulation.
⚠️ Attention: Never use sharp objects to chip ice by hand unless you have a No Frost system. Damage to the evaporator will lead to freon leakage and a characteristic hissing sound, which can be confused with a crash.
Regularly defrost the refrigerator (if required by the model) and wash the drainage hole. A clogged drain can lead to the accumulation of water, which, as it freezes and thaws, will create ice jams and additional sounds. Keep the rear of the condenser clean: dust impairs heat transfer, causing the compressor to work harder and noisier.
Frequently asked questions (FAQ)
Why does the refrigerator only crack at night?
At night, the overall noise level in the apartment decreases, and you begin to notice sounds that were invisible during the day. In addition, at night the voltage in the electrical network may stabilize or, conversely, jump, which affects the operation of the compressor. Also at night, cyclic switching on and off occurs more often, accompanied by thermal expansion of materials.
Is it dangerous if a new refrigerator cracks?
In 90% of cases, this is normal for a new unit. There is a “grinding in” of parts, shrinkage of materials and adaptation to temperature conditions. If the crackling sound is not accompanied by a lack of cold or a burning smell, simply observe the equipment for 1-2 weeks.
Can the crackling noise be the cause of an electrical fault?
Yes, unstable voltage or poor contact in the outlet can cause sparking, which is heard as a crackling sound. Check the plug and socket for heat. If they are hot, the problem is in the wiring, not in the refrigerator.
What to do if a strong cracking sound appears after defrosting?
Most likely, there was ice left inside, which began to actively melt and break off when turned on, or you did not assemble the drawers correctly and they are rubbing against the walls. Let the refrigerator dry completely and check the assembly.
How to distinguish the crack of plastic from the crack of a compressor?
The crack of plastic is usually more loud, high-pitched and chaotic. Compressor sounds are lower, dull, often rhythmic and come from the lower rear of the case. Place your hand on the back wall below: if vibration and sound come from there, it’s the motor.