The appearance of extraneous sounds in household appliances always causes concern for the owner, especially if we are talking about refrigerator compartmentwhich operates 24 hours a day. A characteristic crackling noise can occur at different moments: immediately after switching on, during active operation, or during the compressor's idle period. It is important to understand that not every sound indicates a breakdown, and there is no need to panic ahead of time.
In this article we will analyze in detail the physical and mechanical causes of the crackling sound, and explain the difference between normal operation of the system and signs of a malfunction. You will learn how to independently diagnose the source of noise, be it thermal expansion of materials or a serious problem with motor-compressor.
Before disassembling the unit or looking for the service center number, you need to analyze the nature of the sound and the conditions for its occurrence. Often the problem is solved by simply adjusting the position of the housing or replacing a worn part, which is easy to find on sale. Ignoring some types of noise can lead to more expensive repairs in the future.
Natural physical processes: cracking during cooling and heating
The most common and absolutely safe cause of cracking is thermal expansion compression of materials. The inner walls of the chamber, the evaporator and the plastic trays constantly change their temperature over a wide range. During sudden cooling, the plastic contracts, emitting characteristic clicks, which many confuse with a crash.
This sound is especially often heard in models with a system No Frostwhere defrosting cycles occur automatically. The moment the defrosting heating element turns on, the cold plastic of the evaporator begins to heat up sharply, which causes a series of loud clicks. This is a normal situation that does not require intervention.
If your refrigerator is made of metal inside and the shelves are made of glass or plastic, the difference in expansion coefficients will cause rubbing sounds against each other. Typically, such sounds do not last long and fade away as soon as the temperature stabilizes. In new devices, this process can be heard more clearly due to the lack of wear in the fasteners.
⚠️ Attention: If the crackling sound is accompanied by the smell of burning or melted plastic, immediately unplug the device. This may indicate overheating of the wiring or melting of the insulation, which is a fire hazard.
The intensity of the sounds depends on the quality of the materials used by the manufacturer. Cheap plastic tends to crack louder than high-quality polymers. Over time, after several years of operation, the frequency of such sounds usually decreases, as the materials undergo primary “shrinkage.”
Problems with the motor-compressor: when the hum turns to crackling
The heart of the refrigerator is compressorwhich circulates the refrigerant. In good condition, it emits a smooth, low-frequency hum. However, if you hear a metallic crackling, clanging or knocking noise precisely when the engine starts or stops, this is an alarming signal.
One of the reasons may be wear on the internal mechanical parts of the compressor, such as the piston group or valves. When a part reaches the end of its life, the gaps increase and the parts begin to hit each other. This sound is often described as a “metal clanging” or “ball rolling.”
Another reason is a problem with the start relay. If the contacts burn out or the mechanism sticks, an attempt to start the engine is accompanied by a loud cracking and clicking sound, after which the engine may not start or may turn off immediately. In this case, replacement is required start protection relay.
- 🔊 A loud metallic clang at start indicates mechanical destruction of the compressor components.
- ⚡ Frequent clicks without starting the motor indicate a malfunction of the starting relay or windings.
- 📉 Increasing noise over time indicates progressive wear of bearings or bushings.
Diagnostics of the compressor requires caution. If you do not have the skills to work with electrical appliances, it is better not to open the casing yourself. Incorrect connection can lead to a short circuit or damage to the motor windings.
No Frost system fan: ice and foreign objects
In refrigerators with the system No Frost the fan is responsible for circulating cold air. If you hear a crackling sound that sounds like a propeller hitting something hard, the problem most likely lies in this unit. The blades may touch frozen ice or a foreign object.
A frequent situation is the formation of a “fur coat” on the evaporator due to the door not being tightly closed or a malfunction of the defrost sensor. Ice builds up and begins to interfere with the rotation of the impeller. As a result, the fan emits an intermittent crackling or humming sound, which may increase over time.
Small objects could also get into the air duct channels: fruit pits, pieces of foil or labels. When the fan is turned on, the air flow picks them up and they begin to hit the walls of the channel or blades. To fix this, you will have to disassemble the back wall of the chamber.
⚠️ Attention: Before checking the fan, be sure to disconnect the refrigerator from the power supply. Rotating blades can cause injury, and contact with electrical components with wet hands is life-threatening.
If the fan makes a dry cracking sound without touching, the grease in the sliding bearing may have dried out or the motor itself may have failed. In such cases fan subject to replacement, since these components are usually not subject to repair.
Deformation of the housing and violation of the installation geometry
Sometimes the source of the crackling noise is located outside. If the refrigerator is not installed level, on an unstable floor, or is tilted, the cabinet may be subject to constant stress. When the compressor operates, vibration occurs, which is transmitted to the shelves, drawers and the box itself, causing a resonating crackling sound.
Check the adjusting supports. They should fit snugly to the floor, ensuring a stable position. If one of the legs is hanging in the air, the slightest movement or vibration from people passing by will cause displacement and characteristic sounds.
It is also worth inspecting the space around the refrigerator. The rear grille of the condenser should not touch the wall or furniture. Vibration from a running unit causes metal tubes to hit hard surfaces, creating an unpleasant rattling sound.
- 🏗️ Check the horizontal installation using a building level.
- 🧱 Make sure that there is a gap of at least 5-7 cm between the back wall and the wall of the room.
- 📦 Remove foreign objects lying on the refrigerator lid or close to the sides.
☑️ Installation diagnostics
It is important to consider that in corner apartments or houses with thin floors, vibration can be transmitted through the building structures, enhancing the effect. In such cases, it is recommended to use anti-vibration stands for supports.
Internal elements: shelves, drawers and fastenings
The source of noise does not always lie in complex technical components. Often the cracks themselves shelves, plastic containers for vegetables or door barriers. The plastic dries out over time, and with temperature changes it begins to make friction sounds at the fastening points.
Pay attention to the guides for the drawers. If they are skewed or have been exposed to liquid that has frozen, there will be a crunching sound when pulling out and installing the drawer. Lubricating with food grade silicone or replacing damaged shelves solves the problem.
Glass shelves can also be a source of sound if they do not fit tightly in the grooves or have cracks. The resonance from the compressor causes the glass to vibrate, creating a ringing or crackling sound. Placing a thin rubber gasket under the glass often eliminates noise.
| Element | Nature of sound | Probable cause | Solution |
|---|---|---|---|
| Plastic tray | Sharp cracking | Thermal expansion | Normal, will go away on its own |
| Glass shelf | Ringing, rattling | Vibration, loose fit | Correct, place a gasket |
| Door barrier | Creak, crackling | Overfilled, deformed | Unload, replace |
| Box for vegetables | Crunch when moving | Ice on the guides | Defreeze, dry |
Why does plastic crack more in winter?
In winter, humidity in apartments are lower, and the temperature difference between the street and the room is greater. This leads to more intense compression of materials and increased frequency of sounds of thermal expansion.
When a cracking indicates a serious breakdown
There are situations when sounds cannot be ignored. If the cracking sound is accompanied power outage throughout the entire apartment or knocking out plugs, it means that there is a short circuit in the refrigerator circuit. This may be a breakdown of the compressor insulation or a wiring fault.
Another critical sign is the appearance of a crackling sound along with loss of cold. If the engine hums and crackles, but the temperature in the chambers does not drop, there may be a pipe break or valve failure. In such cases, operating the device is pointless and dangerous.
A sharp, single bang, similar to a shot, may indicate a rupture of the refrigerant tube. This often happens due to corrosion or mechanical damage. After such a sound, the refrigerator stops freezing, and a chemical smell may appear inside.
⚠️ Attention: If you hear a loud bang and smell gas or chemicals, urgently ventilate the room and do not turn on electrical appliances. The refrigerant may be flammable or toxic.
Timely contacting a service center if these symptoms are present will save you from buying a new refrigerator. Repair at an early stage is often cheaper than replacing a burnt-out compressor or restoring the system after defrosting food.
Methods of prevention and care of equipment
To minimize the amount of extraneous sounds and extend the life of the unit, it is necessary to properly care for it. Regular defrosting (for drip systems) or cleaning of the drainage hole will prevent the formation of excess ice, which often causes the fan to crack.
Make sure that the door sealing rubber seals tightly. If warm air enters the chamber, the humidity inside increases, more ice forms, and the system works overload. Wipe the seal with a soft cloth and check its elasticity.
Do not overload the shelves with heavy objects. Excess weight can cause plastic fixtures and shelves to become deformed, causing them to move and cause squeaks. Distribute the food evenly throughout the entire volume of the chamber.
Remember that modern refrigerator models are equipped with many electronic sensors and mechanisms. Taking care of equipment and following the operating instructions is the best prevention of any problems, including noise.
Is it normal if the refrigerator cracks immediately after turning it off?
Yes, this is absolutely normal. When the compressor stops, the pressure in the system equalizes, and the materials (plastic, metal) begin to cool or, conversely, heat up from the heat of the motor. Thermal expansion causes characteristic clicks and crackling sounds that last from a few seconds to a couple of minutes.
Can a new refrigerator crack?
Yes, new refrigerators often make more noise in the first weeks of operation. The grinding of mechanical parts, shrinkage of materials and adaptation of internal components to operating temperatures occur. If the sound is not a metallic clang and is not accompanied by malfunctions, there is no need to worry.
What should you do if the cracking noise intensifies after defrosting?
Make sure that you completely dry the camera before turning it on. Residual water could get into the mechanisms or freeze where the fan rotates. Also check whether the shelves and drawers are level after cleaning. If the sound is strange and does not go away after a day, contact the service.
Does the voltage level in the network affect the crackling sound?
Low or unstable voltage can cause problems with starting the compressor. The engine may hum, crackle and try to start, but will not gain momentum. In such cases, it is recommended to use a voltage stabilizer to protect equipment from overloads.