The situation when the refrigerator starts make extraneous sounds, often takes the owner by surprise and causes concern. Clicks, knocks and crackles can be both a sign of normal operation of the equipment and a signal of a serious malfunction that requires immediate attention. It is important to learn to distinguish harmless sounds from those that indicate a breakdown in order to prevent damage to products or failure of equipment.
In this article we will analyze in detail the physical and technical causes of noise in various components of the refrigeration unit. You will learn how diagnose the problem by the nature of the sound, when you can handle it yourself, and in which cases it is better to call a specialist. Understanding the structure of your device will help save time and money on repairs.
Physical causes: expansion of materials and thermal noise
The most common and absolutely safe cause of clicking is thermal expansion. The internal walls of the refrigerator, especially in models with the No Frostsystem, are made of plastic. When there is a sudden change in temperature during freeze or defrost cycles, the material contracts and expands, producing characteristic clicking sounds.
These clicks usually occur at regular intervals and can be heard even after the compressor is turned off. If the sound resembles crackling or popping, and the temperature inside the chamber is maintained stable, then thermal noise does not pose any threat.
- 🔊 The sound occurs mainly immediately after turning the motor on or off.
- 🔊 Character of clicks: ringing, short, sometimes with an echo.
- 🔊 The intensity of the sound may depend on the humidity in the room.
It is worth noting that in new refrigerators such sounds may be more audible, since the plastic has not yet gone through the full shrinkage cycle. Over time, the frequency of these clicks may decrease, but they usually do not disappear completely. This is a feature of the physics of materials, and not a manufacturing defect.
Operation of the starting relay and electrical circuit
One of the key elements of the starting system is start relay. It is this component that is responsible for supplying voltage to the compressor windings and its subsequent shutdown when the required parameters are reached. The sound the relay makes is often described as a loud, distinct click.
During normal operation, you may hear one click when the engine starts and one when it stops. However, if the clicks become frequent, in series, or are accompanied by a hum that ends abruptly, this may indicate relay malfunction or problems with starting the motor.
If the relay is worn out or dirty, the contacts may stick or spark, which leads to a characteristic crackling sound. In such cases, the compressor may try to start several times, making a series of clicks, before either starting up or going into protection.
⚠️ Attention: If you hear a series of rapid clicks, followed by silence, and the refrigerator stops cooling, immediately unplug the appliance. This is a sign that the starting device cannot start the motor, and further attempts may lead to burnout of the windings.
The nature of the compressor and motor operation
The compressor is the “heart” of the refrigerator, and its operation is rarely completely silent. Modern inverter models are much quieter than classic ones, but even they can make sounds. It is important to distinguish between normal operating hum and mechanical shocks.
If clicks come directly from the rear of the unit where the motor is located and have a dull, metallic tint, this may indicate internal problems. Wear of the piston group or valves is often accompanied by a clattering sound, which intensifies as the engine warms up.
- 🔊 Dull knocks may indicate wear of the internal bearings.
- 🔊 A metallic clanging sound is often associated with loose housing mounting bolts.
- 🔊 A rhythmic clicking sound may be a sign of valve malfunction.
In some cases, the compressor housing itself may vibrate slightly and touch nearby pipes or niche walls, creating a knocking effect. Checking the fastening of the motor and shock absorbers often helps eliminate this defect without complex repairs.
Defrost and defrost system (No Frost)
Refrigerators with the system No Frost are equipped with an automatic defrost system that periodically removes ice from the evaporator. This process may also be accompanied by specific sounds, which users often confuse with a breakdown.
During defrosting, the heating element turns on and melting ice may drip into the pan, making a hissing or gurgling sound. However, sometimes pieces of ice, when thawing, can fall off the fan or damper with a crash, creating a loud click or impact.
Why does ice click?
Ice that builds up on the evaporator changes its structure and volume when heated. The sudden separation of a block of ice from the surface or fan blades causes a sound boom that is transmitted through the housing.
If the defrosting system does not work correctly, for example, the drainage is clogged or the heating element is faulty, ice can accumulate in large volumes. In this case, periodic clicking noises will become louder and more frequent, as massive pieces of ice will constantly interfere with the operation of the fan.
Diagnosing this problem often requires a visual inspection of the evaporator. If you notice that clicks become more frequent after a long period of operation without defrosting, the unit may require manual defrosting to reset the system error.
External factors: vibration and installation
Often the source of annoying clicks and knocks is not internal mechanisms at all, but external factors. Incorrect installation of the refrigerator or contact with surrounding objects can create a resonance that enhances any operating sounds.
Check whether the refrigerator body is touching the wall, furniture or curtains. Even the slightest touch when the compressor vibrates will be transmitted to other objects, creating the effect of constant rattling or tapping. It is also important to check the installation level.
☑️ Diagnosis of external causes of noise
Inside the chambers, glass shelves or dishes can become a sound source. If the shelf does not lie tightly in its grooves, it may bounce and make loud knocks when the motor is running. Bottles that are too close to each other on the door behave similarly.
Make sure that the refrigerator is strictly horizontal. Using a building level will help identify misalignment. Adjusting the front legs allows you to compensate for uneven floors and eliminate swaying, which often causes knocking.
Diagnostic table: identify the problem by sound
To simplify the diagnostic task, we have compiled a summary table that will help you classify the sound you hear and suggest its source. Remember that an accurate diagnosis can only be made by a specialist with equipment.
| Sound type | Probable cause | Degree of danger | Actions |
|---|---|---|---|
| Single loud click | Thermal expansion of plastic or relay operation | Safe | No supervision required |
| Series of frequent clicks | Faulty start relay or protection motor | High | Disconnect from the network, call a technician |
| Metallic knock from behind | Compressor wear or contact with pipes | Medium/High | Check the motor mounting |
| Crackling inside the chamber | Fan operation or defrosting No Frost | Safe | Check products and shelves |
| Humming with vibration | Incorrect installation or contact with wall | Safe | Move the refrigerator, level |
Using this table, you can initially assess the condition of your appliance. If the nature of the sound matches the description of high danger, do not delay contacting the service center.
When you need to call a technician
There are a number of situations when self-repair is not only ineffective, but also dangerous. If you determine that the clicks are associated with an electrical part or a sealed circuit, it is better to entrust the work to professionals.
A particularly alarming signal is the appearance of a burning smell along with frequent clicks of the relay. This indicates overheating of the wiring or motor windings. You should also be wary if the refrigerator has stopped freezing, but continues to make strange sounds.
⚠️ Attention: Never try to open the sealed circuit of the refrigerator yourself or repair the compressor without the appropriate qualifications and equipment. This can lead to freon leakage and electric shock.
The technician will be able to carry out accurate diagnostics using pressure gauges and testers, replacing failed components with original spare parts. Professional repairs guarantee the restoration of tightness and proper operation of the system.
Noise prevention and care of equipment
To minimize the risk of extraneous noise in the future, it is important to follow the rules for operating the refrigerator. Regular defrosting (for models without No Frost) and cleaning the drainage system will help avoid problems with ice plugs.
Make sure that the rear condenser grille is always clean. Dust and animal hair that accumulate there impair heat transfer, causing the compressor to work with increased load, which can lead to overheating and noisy operation.
Also, do not overload the shelves and doors. Uneven weight distribution can lead to skew of the case and disruption of the geometry of the doors, which will cause knocking when they are closed or vibration.
Understanding the nature of the sounds made by your refrigerator, allows you to remain calm and act rationally. Most clicks are a normal part of the operating cycle, but paying attention to changes in the background sound will help you notice the problem in time.
Frequently asked questions (FAQ)
Why does the refrigerator click when it is turned off?
Clicks when the refrigerator is turned off are most often caused by thermal expansion or contraction of plastic elements housing and internal chambers. It could also be the sound of cooling metal or residual processes in the system if a little time has passed since the shutdown.
Is it dangerous if the relay clicks every 5-10 minutes?
Yes, it can be dangerous. Frequent turning on and off (clocking) indicates problems with the thermostat, a freon leak, or a malfunction of the start relay. This mode of operation quickly wears out the compressor and requires diagnostics.
Can you continue to use the refrigerator if it clicks?
If the clicks are rare and the temperature inside remains normal, you can use it. If the clicks are frequent, loud, accompanied by a lack of cold or a burning smell, operation must be stopped until the reasons are determined.
How to reduce the noise from the refrigerator yourself?
Check the installation: the refrigerator should not touch the walls. Level the legs. Make sure nothing rattles inside (dishes, shelves). Move the unit 5-10 cm away from the wall for better ventilation.