The appearance of extraneous sounds in the operation of household appliances always causes concern for the owner. The refrigerator, which previously worked silently, suddenly begins to make strange crackling sounds, clicks or hums, which disturbs the silence in the apartment. Many users immediately begin to panic, assuming a serious breakdown of an expensive unit and preparing to call a technician. However, noise does not always indicate a critical malfunction.
Often crackling in the refrigerator is a consequence of natural physical processes occurring inside the cooling system. Understanding the nature of these sounds will help you distinguish normal operation of the device from a real breakdown. In this article we will analyze in detail the main causes of noise, diagnostic methods and ways to fix problems on our own.
It is important to learn to distinguish the nature of the sound, since it is this that tells you which unit requires attention. Plastic cracking is different from the sound of a working one compressorand the noise flowing refrigerant does not resemble clicks thermostat. Competent diagnostics begins with careful listening to the device.
Natural physical processes and thermal expansion
The most common reason why a refrigerator cracks, especially a new one, lies in the materials from which it is made. The inner chamber, shelves and outer casing are made of various types of plastic and metal. When the temperature changes, these materials behave differently: they contract when cooled and expand when heated.
When you have just defrosted the unit or loaded a lot of warm food into it, an active heat transfer process begins. At this moment, you can hear a characteristic crackling sound, reminiscent of the crackling of wood in a fire or clicks. This temperature expansion plastic and metal, which is absolutely normal for any equipment.
⚠️ Attention: If the crackling noise is heard exclusively in the first hours after turning on or defrosting and stops as the temperature rises, this is a normal situation that does not require intervention.
The intensity of such sounds depends on the quality of materials and design of the model. In budget models made of ABS plastic sounds may be louder due to the lower density of the material. Over time, when the parts “grind” together, the frequency of clicks usually decreases, but may not completely disappear.
The influence of humidity on plastic cracking
High humidity in the room can enhance the effect of thermal expansion, making the plastic more susceptible to deformation and, as a result, to making sounds.
Operation of the defrost system and refrigerant circulation
Modern refrigerators operating on the system No Frost or Full No Frosthave a complex defrosting cycle. Unlike old models, where the ice melted naturally, here a timer is responsible for the process. Periodic switching on of the heater causes a sharp change in temperature in the evaporator, which is also accompanied by sounds. The defrost heating element and timer. Periodic activation of the heater causes a sharp change in temperature in the evaporator, which is also accompanied by sounds.
In addition, the refrigerant (freon) itself circulating through the tubes, when transitioning from a liquid to a gaseous state and back, makes sounds similar to gurgling or slight hissing. Sometimes these sounds may be accompanied by rare clicks when the pressure in the system equalizes after stopping the engine.
- 🌡️ Heating Defrost heating element causes expansion of the evaporator metal.
- 💧 The dripping of melting ice into the pan may sound like a rhythmic knocking.
- 🌬️ The movement of air in the system No Frost sometimes masks light crackling noises.
Particular attention should be paid to the moment the engine stops. At this time, the pressure in the circuits is equalized, and valve may make a loud click. This is a necessary process to facilitate the next start of the compressor. If the refrigerator cracks exactly when the motor is turned off, this is a good sign.
Faults in the compressor and start relay
The situation changes when the crackling noise becomes metallic, loud and repetitive. In this case, the source of the problem is often compressor the “heart” of the refrigerator. If the motor is worn out, its internal parts can knock against each other, creating vibration and noise.
A frequent cause of a rattling noise when trying to start is a malfunction start-up protection relay. This small element is responsible for starting the engine. If the relay contacts are burnt or the mechanism is jammed, you will hear a series of quick clicks, after which the motor will either start with difficulty or go into protection.
⚠️ Attention: If you hear a loud metallic clang or crackling directly from the motor-compressor, and the refrigerator has stopped freezing, immediately unplug the device to avoid winding combustion.
You can diagnose the problem by listening to the back of the unit. If the cracking sound is accompanied by strong vibration of the housing, the mounting bolts of the compressor itself or the shock-absorbing springs on which it is suspended may have become loose. In such cases, the motor begins to bang against metal tubes or the housing.
Problems with the fan in No Frost models
In refrigerators with a system No Frost the fan is responsible for circulating cold air. Impeller blades can become dirty or deformed over time. If threads are wound around the axle or a piece of ice gets in, the fan will begin to make a cracking or humming sound.
Sometimes the cause is wear of the fan bearings. In this case, the sound increases gradually: at first it is a slight hum, turning into annoying friction and crackling. This is especially audible when the door is closed, since in many models the fan operates only in a closed circuit.
To check, you need to remove the back panel in the freezer (after defrosting the refrigerator). A visual inspection will reveal foreign objects or ice on the blades. Cleaning and lubrication often solve the problem without replacing the part.
Vibration and incorrect installation of the unit
Sometimes a cracking sound is not an internal breakdown, but the result of resonance. If the refrigerator is not level, its legs are not adjusted, or the body touches the wall, vibration from the running motor is transmitted to furniture and building structures, increasing significantly.
Check the distance to the back wall. The condenser tubes (grid at the back) expand when heated and can touch the wall, producing an unpleasant grinding or crackling sound. Vibration can also be transmitted to nearby objects: microwave, shelf or kitchen set.
☑️ Diagnostics of refrigerator installation
It is important to make sure that nothing vibrates inside the chamber. Glass shelves, bottles of liquid or dishes that come into contact with each other can ring and crackle from the slightest vibration of the compressor. Try holding the objects inside one by one - if the sound disappears, then the source has been found.
Comparative table of types of noise
For ease of diagnosis, we have compiled a table that helps classify sounds and determine their source. This will allow you to quickly navigate the situation.
| Sound type | Probable cause | Degree of danger | Actions |
|---|---|---|---|
| Rare clicks of plastic | Thermal expansion | Safe | Observation |
| Loud click when turning off | Relay or pressure equalization | Normal | Do nothing |
| Metallic clanging of the motor | Compressor wear | Critical | Call a technician |
| Fan cracking | Ice or bearing wear | Medium | Cleaning or replacement |
| Rhythmic humming | Touching pipes or walls | Low | Rearrangement |
Analyzing the data from the table, we can conclude that most sounds do not carry fatal threats. However, ignoring metal knocking can lead to expensive repairs or replacement of the compressor. Timely detection of extraneous fan sound can save the evaporator from ice fouling and failure of the heating element.
Methods of elimination and prevention
If you determine that the cracking is caused by unnatural causes, you can try to fix the problem yourself. Check the installation first: use a spirit level to adjust the legs. The case must be stable, without distortions.
If you suspect a fan or ice, complete defrosting will be required. Unplug the refrigerator, open the doors and leave it for at least 12-24 hours. This will allow the ice to completely melt even in hard-to-reach channels of the system No Frost.
⚠️ Attention: Never use sharp objects (knife, screwdriver) to chip ice inside the chamber. Damage to the evaporator will lead to freon leakage and complex, expensive repairs.
If the crackling noise comes from the tubes at the back, carefully (with the device turned off and cooled down) try to slightly bend them away from each other to prevent contact. Do this with extreme caution, as copper tubes break easily.
In the case when simple measures did not help, and you hear a crackling sound compressor or relay, it’s better not to risk it. Repairing these components requires special tools and knowledge. Trying to repair an electrical part yourself can be dangerous.
When you need to call a specialist
There are a number of symptoms in which independent repair is impossible or dangerous. If the crackling sound is accompanied by the absence of cold, the appearance of a burning smell or melted plastic, stop using it immediately.
Also, professional help is needed if the crackling noise is accompanied by frequent turning on and off of the engine (start-stop mode). This indicates problems in the electrical circuit or mechanical part of the engine, which requires replacement of components.
The specialist will conduct diagnostics using instruments, check the pressure in the system, current strength and condition of the windings. This will allow you to accurately determine whether you need to replace the compressor, thermostat, or simply clean the system.
Why can’t you delay repairs?
If the cracking is caused by friction of compressor parts, further work will lead to the appearance of metal shavings in the system, which will clog the capillary tube and filter drier, increasing the cost of repairs in times.
Regular maintenance, proper installation and careful operation will extend the life of your refrigerator. Keep the condenser at the back clean, don't overload the shelves, and make sure the door is closed tightly.
Is it normal for a new refrigerator to crack in the first week?
Yes, it's absolutely normal. New materials (plastic, metal) undergo a process of primary “shrinkage” and adaptation to temperature changes. Active expansion and contraction in the first days of operation causes more frequent clicks, which will become quieter or disappear over time.
Can a cracking sound be a sign of a freon leak?
A freon leak itself is usually silent. However, if, due to a leak, the operating cycle is disrupted and the compressor begins to work without stopping or frequently turns on/off, this may be accompanied by a change in the characteristic sounds of the system.
Why does the refrigerator only crack at night?
At night, the overall noise level in the apartment decreases, and you simply begin to notice sounds that were drowned out by household noise during the day. Also, at night, the voltage in the network may drop, which affects the operation of the electric motors, or the temperature in the room changes.
Is it dangerous to ignore the crackling sound of the relay?
If the relay clicks, but the refrigerator freezes, this may be a variant of the norm (cyclical operation). But if the clicks are frequent, but there is no cold, or the relay is cracking continuously, this is dangerous, since the compressor may burn out or a fire hazard may arise due to overheating of the contacts.
How to distinguish the cracking of ice from a breakdown?
The cracking of ice (especially in the freezer) usually sounds like a dull crunch or the crack of breaking wood and occurs periodically. The sound of a breakdown (metallic knocking, squealing, rattling) has a different tone and often depends on the operating mode of the motor, and not on defrosting cycles.