Extraneous sounds that arise during the operation of household appliances always cause concern among owners. If the refrigerator begins to crack, this can signal both minor temporary changes and serious breakdowns that require immediate attention. Many users mistakenly believe that any noise is a sign of compressor failure, but the real picture often turns out to be much more complex and multifaceted.
In this article we will analyze in detail the physical and technical reasons for the crackling noise characteristic of various types of cooling devices. Understanding the nature of the sound will help you quickly determine whether you need urgent help from a technician or whether the problem can be fixed yourself by simply changing the operating conditions or making a simple adjustment.
It is important to consider that modern models Liebherr, Bosch or LG equipped with complex refrigerant circulation and temperature control systems that can produce specific sounds that are not typical old units. Therefore, before you panic, it is necessary to analyze the nature of the sound, the frequency of its occurrence and related factors.
Physics of the process: thermal expansion of materials
The most common and absolutely safe cause of crackling is the natural thermal expansion and contraction of materials. The internal volume of the refrigerator and freezer is constantly subject to temperature changes. The plastic, metal and glass from which the shelves and walls are made have different coefficients of expansion.
When the compressor is turned on or off, the temperature inside the chambers changes sharply. At this moment, the materials “walk”, emitting characteristic clicks or crackling sounds. This is especially often observed in models with a system No Frostwhere defrost cycles occur regularly.
New devices may crack louder in the first few weeks of operation, until the materials “grind” to each other. If the sound resembles rare crackling of wood or snapping of fingers, most likely everything is fine with your refrigerator.
- 🔊 The sound appears immediately after turning the motor on or off.
- 🔊 The crackling sound comes from inside the chamber, and not from behind the unit.
- 🔊 The intensity of the noise depends on the temperature changes in room.
⚠️ Attention: If the crackling sound is accompanied by a strong burning smell or smoke, immediately unplug the device. This may indicate overheating of the wiring or melting of the insulation.
Often users confuse the natural sounds of plastic expansion with a breakdown, although in fact this is normal operation. Designers create gaps between parts precisely to compensate for these physical processes.
Improper installation and vibration of the housing
The second most common cause of extraneous noise is a violation of installation rules. A refrigerator is a complex mechanism in which a compressor creates vibration. If the case is not level or touches the wall, this vibration is transmitted to furniture and building structures, increasing significantly.
Check whether the unit is on a level surface. Even a slight misalignment can cause one of the legs to be raised and the body to be skewed. This causes displacement of the internal parts and a characteristic crackling sound when the motor is running.
The distance to walls and furniture is also important. The rear condenser grille should not touch wallpaper or cabinets. When heated and vibrating, contact with foreign objects causes rattling and crackling.
☑️ Installation diagnostics
Sometimes the cracking sound is caused by the fact that the dishes or food inside are poorly secured. Glass bottles touching each other on a vibrating shelf can make sounds very similar to a mechanism breakdown.
Problems with the No Frost system and defrosting
In refrigerators with the system No Frost there is a fan and a defrost heater. It is these elements that often become the source of a specific crackling noise. During operation, ice freezes on the evaporator, which must be periodically removed.
When the defrosting heating element is turned on, the ice begins to melt and flow into the drainage system. Chunks of ice may break off and fall onto the heater or tray, making a loud cracking or breaking glass sound. This is normal if it occurs cyclically.
However, if the ice crust builds up too much, it can block the fan blades. In this case, the fan begins to “gnaw” the ice, producing a loud, intermittent crackling sound. This already requires intervention: complete defrosting of the unit is necessary within 24 hours.
| Symptom | Possible cause | Action |
|---|---|---|
| Rare crackling noise when turned off | Thermal expansion | Do nothing, this is normal |
| Constant crackling + humming | The fan touches the ice | Defreeze 24 hours |
| Crackling + knocking from behind | Vibration of the case | Align the legs |
| Loud crackling + does not freeze | Compressor malfunction | Call a technician |
⚠️ Attention: In models with No Frost you cannot use sharp objects to remove ice. Damage to the evaporator will lead to a freon leak and costly repairs.
A malfunction of the defrost sensor or timer can result in ice not having time to melt, accumulating and causing constant noise when the fan operates. In such cases, replacement of failed elements is required.
Mechanical malfunctions of the compressor
The compressor is the heart of the refrigerator. If the crackling comes from it and is metallic, ringing in nature, this is an alarming sign. In normal condition, the engine hums evenly, without sudden jumps and impacts.
Crackling noises can occur due to wear of the internal valves or piston group. Metal parts begin to hit each other, creating a characteristic sound. Most often this happens in older models or when operating at maximum capacity.
Is it possible to repair the compressor yourself?
Repairing the compressor yourself at home is almost impossible. Special equipment is required to evacuate the system and pump in freon. An attempt to open it will lead to a complete loss of the tightness of the circuit.
Another reason is the loosening of the mounting bolts on which the motor is installed. The vibration causes it to hit the metal casing or tubes, causing loud clanging and cracking noises. Sometimes it is enough just to tighten the fasteners or install rubber gaskets.
If the compressor makes a cracking noise only at the moment of startup, and then runs quietly, the problem may be in the start relay. It may “click”, trying to start the engine, but not being able to cope with the load. Ultimately, the unit may stop turning on completely.
Defects in piping and refrigerant circulation
The pipes through which the refrigerant circulates can also be a source of noise. When freon moves under pressure in the tubes, turbulence, gurgling or hissing may occur. This is normal operation, especially immediately after switching on.
However, if the tubes are too close to each other or touch the housing, vibration from the gas flow will cause them to collide. This leads to constant metallic crackling or rattling, which intensifies when the engine is running.
Sometimes cracking occurs due to oil getting into the circuit or the presence of air in the system (if unqualified repairs were carried out). In such cases, the sound may be sharper and accompanied by unstable operation of temperature conditions.
It is important not to overdo it with physical impact on the tubes. Copper is a soft metal and can be easily damaged, causing gas leakage. All manipulations must be carried out with extreme caution.
When it is necessary to call a specialist
There are a number of symptoms in which independent actions can only aggravate the situation. If you notice that a cracking sound is accompanied by an increase in temperature in the chambers, this indicates a violation of the cooling cycle.
The appearance of oily stains under the refrigerator or on the back wall is also a reason to call a specialist. This is a direct sign of depressurization of the system, requiring professional intervention and sealing of the circuit.
Do not ignore the smell of burnt wiring. If the crackling noise comes from the electrical compartment and smells like burnt plastic, further plugging in may result in a fire. In such cases, repairs are required immediately.
Modern diagnostics allow you to quickly identify the cause: the technician uses a thermal imager to search for leaks and a pressure gauge station to check pressure. It is impossible to carry out these procedures on your own without equipment.
Why does a new refrigerator crack more than the old one?
New models often have more powerful compressors and thin walls to increase the usable volume. This may increase vibration transmission. In addition, new materials may make sounds when “grinding in” in the first weeks.
Is it possible to lubricate rubbing parts with oil?
It is absolutely not possible. Grease can destroy plastic, cause a fire if it comes into contact with electricity, or damage rubber seals. Use only dry control methods.
Does the temperature in the room affect the crackling noise?
Yes, in a hot room the compressor works harder and turns on more often, which increases the number of thermal expansion cycles. Also, a hot environment can cause expansion of the plastic elements of the case.
Is it dangerous to ignore the crackling sound of a fan?
If the fan touches ice, it can burn out or break the blades. This will lead to the cessation of cold air circulation and spoilage of food, as well as failure of the fan motor.
How to distinguish the cracking of ice from a breakdown?
The cracking of ice usually sounds like the ringing of falling pieces or crunching. Mechanical failure often sounds like a metallic knock, grinding or rhythmic beating, synchronous with the operation of the motor.