The situation when the refrigerator periodically clicks is familiar to many owners of household appliances. Sometimes these sounds are subtle and occur rarely, but in other cases they become intrusive and loud, causing concern about the health of the unit. It is important to understand that not every knock or click indicates a breakdown, but you should not ignore them completely either.
Modern models of refrigeration units are complex electromechanical systems in which many components interact with each other. Compressor, thermostat, start relay, defrosting system - all these elements can make sounds during normal operation or signal a malfunction. The ability to distinguish normal from pathology will help you save time and money on calling a specialist.
In this article we will analyze in detail the main causes of extraneous sounds. We will consider both natural processes in the cooling system and technical faults that require intervention. You will learn how to carry out initial diagnostics on your own and when to sound the alarm.
Natural physical processes in the cooling system
Before you panic, you need to rule out physics. The refrigerant circulating through the tubes constantly changes its state of aggregation, passing from gas to liquid and back. This process is often accompanied by sound effects, which an inexperienced user may mistake for a breakdown. Thermal expansion materials also contribute to the overall acoustic picture.
Microscopic deformations of plastic or metal can occur inside the chambers and on the back wall due to temperature changes. When the refrigerator turns on or off, the temperature of the elements changes sharply, causing a characteristic clicking sound. This is absolutely normal for most models, especially if they are not installed level or have glass shelves that can also react to vibration.
Particular attention should be paid to the sounds that occur immediately after turning off motor. At this point, the pressure in the system equalizes, and the refrigerant can “gurgle” or “shoot” in the evaporator tubes. If your refrigerator makes such sounds, but still freezes perfectly, then everything is probably fine with it.
Operation of the start relay and electrics
One of the most common causes of loud clicks is the operation of start relay. This small component is responsible for starting the compressor motor. It is the relay that supplies the impulse necessary to start the motor and produces a characteristic click. If a sound is heard when the refrigerator is turned on, this is usually a normal situation.
However, the nature of the click may change. If you hear a series of quick clicks, after which the engine hums but does not start, or is completely silent, this is an alarming symptom. In such cases, the relay itself is often to blame, as it could “stick” or fail. Also, the problem may lie in the motor windings or power surges in the network.
⚠️ Attention: Frequent attempts to start the motor with loud clicks can lead to burnout of the compressor windings. If you notice such cyclical behavior, it is better to temporarily disconnect the appliance from the network until the technician arrives.
The electrical system of the refrigerator is sensitive to the quality of the voltage. Network surges can cause false alarms of protective mechanisms, which are also accompanied by sound signals. To protect expensive equipment, it is recommended to use voltage stabilizers, especially in houses with old wiring.
Malfunctions of the thermostat (thermostat)
The thermostat is the “brain” that decides when the refrigerator needs to cool the chamber and when you can rest. The principle of its operation is simple: it closes and opens an electrical circuit depending on the temperature inside the chamber. The moment the contacts are switched is often accompanied by a distinct click.
If the clicks begin to sound too often, the thermostat may be set incorrectly or is faulty. In some models, especially older ones, mechanical thermostats may rattle or click even without changing the operating mode. This occurs due to wear of the contact group or weakening of the spring.
- 🔹 Frequent switching on: If the click is heard every 2-3 minutes, check the temperature settings. You may have set the mode too low.
- 🔹 Lack of response: If there is no click at all and the refrigerator does not turn on, the thermostat could be completely out of order.
- 🔹 An extraneous crackling sound: Sometimes sparking may occur inside the regulator itself, which can be heard as quiet crackling.
Replacing the thermostat is not the most difficult procedure, but it requires precision. It is important to choose a model with similar characteristics, since the length of the capillary tube and the temperature range may vary between different manufacturers.
How to check a thermostat without instruments?
Disconnect the wires from the thermostat and short them directly (observing safety precautions!). If the refrigerator starts and freezes, the problem is in the thermostat. If not, look for the reason in the compressor or relay.
Problems with the compressor and its mounting
The compressor is the heart of the refrigerator. If it does not work correctly, this is immediately reflected in the sound background. Water hammer, which occurs when liquid freon enters the compressor cylinder, can cause a loud knock. This is a serious problem, often requiring replacement of the unit.
Another common cause of noise is vibration. If shock absorbers, on which the motor is mounted, are worn out or weakened, the compressor begins to beat against the housing or tubes. As a result, you hear not just a hum, but rhythmic blows or clicks that coincide with the operation of the engine.
| Type of sound | Probable cause | Need for repair |
|---|---|---|
| Single click at start | Normal operation of the relay | Not required |
| Series of clicks, the motor does not start | Malfunction of the starting relay or compressor | High |
| Loud knocking inside the engine | Water hammer or wear of the piston group | Critical |
| Vibration and rattling | Weakening fastenings or touching the tubes | Medium |
It is also important to check whether the refrigeration circuit tubes are touching each other or the housing. When the compressor operates, they vibrate, and if the gap is minimal, a metallic clanging sound occurs. Sometimes it is enough to simply gently move the tube with your hand (always with the appliance turned off!) to fix the problem.
The influence of the No Frost system and defrosting
In refrigerators with the system No Frost the number of noise sources increases. This is where fans and defrost heaters are added. Periodic clicks may be associated with the operation of defrost timerwhich switches cooling and defrosting modes.
The fan circulating air may also make sounds. If ice has frozen on the blades or hub, or if the fan (bearing) has worn out, you will hear cracking or clicking noises. Often such sounds intensify when you open the door, since in many models the fan should stop when the door is opened, but if the mechanism is stuck, the sound may change.
☑️ Diagnostics of the No Frost system
Ice freezing on the evaporator is another reason. Ice may chip and fall onto rotating parts or simply crack when heated. Regular defrosting (even for the No Frost system, at least once a year) helps to avoid such problems and extend the life of the equipment.
External factors and operating conditions
The reason does not always lie inside the unit. Sometimes the refrigerator clicks due to improper installation. If the floor is uneven and the legs are not adjusted, the body will warp. This creates tension in the metal, which is “released” by clicks. In addition, a skewed compressor works under increased load.
Proximity to walls or furniture also plays a role. The rear grille of the condenser should not touch the wall, otherwise the vibration will be transmitted to the furniture, causing resonance and additional sounds. The recommended distance to the wall is at least 5-10 cm.
⚠️ Attention: Make sure that there are no foreign objects (rags, bags) on the back wall of the refrigerator. They can get into the vibration zone of the compressor or touch hot pipes, creating an unpleasant crackling sound.
It is also worth checking the contents of the refrigerator. Glass bottles or dishes placed close to each other or to the walls of the chamber may jingle and click from the slightest vibration of the shelves. Try to remove all the products and listen to see if the sound disappears.
When you need to call a specialist
There is a fine line between self-diagnosis and professional repair. If you have checked all external factors, made sure that the installation is smooth and there are no foreign objects, but the clicking does not stop, it’s time to sound the alarm. Especially if other symptoms are added to the sounds.
An urgent call to a specialist is necessary if:
The refrigerator has stopped freezing or the temperature in the chambers is unstable.
The compressor gets very hot (more than 60-70 degrees) or, conversely, remains cold when running motor.
The clicks are accompanied by a burning smell or a buzzing sound that turns into a howl.
The device turns on for a few seconds and immediately turns off.
Attempts to independently disassemble the sealed circuit or replace the compressor without special equipment and skills can lead to final breakdown of the unit and leakage Freon. Repair in such cases will cost much more.
Frequently asked questions (FAQ)
Why does a new refrigerator click in the first days of operation?
New refrigerators often “break in.” Sounds of materials expanding, new compressor running, and thermostat adjustments may be heard. If after 3-5 days the sound does not change and does not become louder, this is normal.
Can the refrigerator click if it is empty?
Yes, it can. An empty refrigerator operates in a more extreme mode, since the products act as a thermal mass (heat accumulator), smoothing out temperature changes. Without a load, the thermostat may turn on and off more often, making more clicks.
Is cracking ice in the freezer dangerous?
Cracking ice as it forms or breaks off is usually not dangerous for appliances, but can be annoying. However, if the ice builds up too quickly, this indicates a loose door seal or a malfunction of the defrost system, which requires attention.
Why does the refrigerator click but does not turn on?
This is a classic sign of a malfunction of the start relay or the compressor itself (jamming). The relay tries to start the motor (click), but cannot, the protection is triggered, and the cycle repeats. Diagnostics of the electrical part is required.