An audible click in the refrigerator is a sound signal that can alert any owner of household appliances. In some cases, this indicates a normal cycle of turning the unit on and off, in others it indicates an electrical circuit or a mechanical problem inside the motor. It is important to learn to distinguish between a rhythmic, barely noticeable clicking sound and loud, alarming knocks that are repeated with frightening regularity. serious malfunction electrical circuit or mechanical problem inside the motor. It is important to learn to distinguish between a rhythmic, barely noticeable clicking sound and loud, alarming beats that repeat with frightening regularity.
Modern models, be it Liebherr, Bosch or Indesit, make sounds during operation, but the nature of these sounds depends on the type compressor and control system. If you notice that the clicks have become louder or their frequency has changed, it is necessary to conduct an initial diagnosis. This will help you understand whether you need to immediately call a technician or whether the problem can be fixed yourself by checking the simplest elements.
In this article we will analyze the main causes of extraneous sounds, from natural thermal deformation of the plastic to failure start relay. Understanding the physics of the processes inside the refrigeration chamber will allow you to make the right decision on further actions and avoid costly repairs in the future.
Natural causes of sounds during operation of refrigeration equipment
A knock or click does not always mean a breakdown. Often this is a consequence of physical processes occurring inside the case. Thermal expansion materials are one of the most common reasons. The walls of the chamber, plastic shelves and metal elements change their size when the temperature changes (for example, after turning off the compressor or when loading warm products). This causes tension in the material, which is released in the form of a sharp sound, similar to a click or crackling.
Especially often, such sounds are produced by new refrigerators or models that have not been defrosted for a long time. A sound reminiscent of the cracking of plastic or glass usually occurs in the first minutes after the compressor stops or when the door is suddenly opened. This is absolutely normal and does not require the intervention of specialists. Over time, when the materials “get used” to temperature conditions, the frequency of such manifestations may decrease.
Another reason is the operation of the system No Frost. In such models, air is constantly circulated, and air duct dampers open and close to regulate the temperature in different compartments. The damper drive mechanism may make a characteristic clicking sound at the moment of switching. Also, the sound can be made by melting ice in the condensate drainage system if drops of water fall on the heating elements of the evaporator.
It is important to listen to the nature of the sound. If these are single, rare clicks that are heard irregularly, most likely your equipment is working properly. However, if the clicks are accompanied by vibration or humming, you should pay attention to the installation of the unit. An uneven floor or the refrigerator body touching furniture or walls can amplify any vibrations, turning them into distinct shocks.
Malfunctions of the starting relay and electrical circuit
If the clicks become intrusive, are repeated in series and the refrigerator does not start or immediately stalls, the problem lies in the electrics. Most often the culprit is start relay. This device is responsible for supplying voltage to the compressor motor windings at the moment of start. If the relay is faulty, it may endlessly try to start the engine, making loud clicking sounds every few seconds or minutes.
Inside the relay there is a coil and contacts. When current is applied, the coil retracts the core, closing the circuit (click), but if the contacts are burnt or the mechanism is jammed, the circuit immediately opens. As a result, you hear a series of clicks: click - pause - click. This condition is dangerous for the compressor, since it does not have time to start, but is under voltage, which leads to overheating of the windings.
Clicks can also be caused by thermostat (thermostat). This sensor monitors the temperature in the chamber and gives the command to turn the compressor on or off. If the contacts inside the thermostat have oxidized or the mechanism has become loose, sparking may occur when the circuit opens, accompanied by a sound effect. In modern models with electronic control, this function is performed by control module, which can also make quiet clicks when switching modes.
⚠️ Attention: If you hear a series of frequent clicks and the refrigerator is not cooling, immediately unplug the device. Prolonged attempts to start a faulty compressor can lead to its combustion and a fire hazard.
Relay diagnostics are often carried out visually and aurally. If, with the back panel removed, you see that the relay gets hot and the clicking continues, it needs to be replaced. This is an inexpensive part and replacing it will often solve the problem completely. However, if after replacing the relay the situation has not changed, the problem may be in the compressor itself.
How to check the start relay yourself?
Remove the plastic casing from the compressor. Carefully remove the relay (usually it is held in place by clips or screws). Shake the relay near your ear: if you hear a knocking or ringing sound inside (like broken ceramic), the trigger socket or mechanical switch is broken. The relay requires replacement.
Problems with the compressor: mechanical and electrical
The compressor is the heart of the refrigerator, and its operation should not be accompanied by loud extraneous sounds. If you hear clicking sounds coming directly from the motor, this may indicate hydraulic shock or mechanical damage to the internal valves. At the moment of startup, the piston group experiences a load, and if the freon has not had time to go into a gaseous state or there is excess liquid in the system, a shock occurs.
Another reason is bearing wear or the engine shaft bushings. Over time, the lubricant dries out and the metal parts begin to rub against each other. This may cause periodic clicking or grinding noises, especially during changes in operating mode or vibration. In inverter models, where the compressor operates constantly, such sounds may be a sign of a failure in the speed control electronics.
There is also the concept of “backlash” of the compressor. If the unit is old, its internal mechanisms may have exhausted their service life. In this case, the clicks may be accompanied by a hum, but the start-up does not occur. Compressor diagnostics requires special tools (tester, pressure gauge), so if you suspect a motor breakdown, it is better to contact a professional.
It is important to note that in some cases the click may emit protective thermal relay, built into the compressor housing. If the motor overheats, the relay opens the circuit (click), protecting the windings from combustion. After cooling, it closes the circuit again (another click), trying to start the engine. Cyclic repetition of this process indicates an overload or malfunction of the motor cooling system.
The influence of the No Frost system and defrosting on the sound background
In refrigerators with the system No Frost or Frost Free there is an additional module - a timer defrost and heating element (heating element). Periodically, usually once every 8-12 hours, the refrigerator goes into evaporator defrost mode. At this moment, the timer switches operating modes, which may be accompanied by a distinct click. This is normal operation and indicates the start or end of a defrost cycle.
However, if the defrost system is faulty, the clicking noise may become more frequent. For example, if the defrost sensor is stuck, the timer may constantly switch, trying to start heating, but immediately receiving an error or termination signal. This results in a series of clicking noises that can easily be confused with a faulty compressor relay. They can be distinguished by the time of occurrence: defrosting problems often appear at certain time intervals.
The fan is also worth mentioning. In the No Frost system, air circulates forcibly. If the fan blades are covered with ice (due to a clogged drain hole) or the fan bearing is worn out, intermittent knocking noises may occur. Although this is more of a noise, at certain resonant frequencies it can be perceived as a clicking sound.
It is important for owners of such models to monitor the condition of the drainage system. If the water does not drain, it freezes and turns into a block of ice. When the heating element is turned on, the ice begins to crack and break off, making sounds similar to shots or loud clicks. Regular defrosting (even for the No Frost system once a year) helps to avoid such situations.
Diagnostics and table of causes of extraneous sounds
To systematize knowledge and help you quickly determine the source of the problem, we have compiled a table of the main symptoms. Pay attention to the combination of sounds and behavior of the refrigerator. This will help the technician over the phone quickly understand the essence of the problem or tell you what part to look for in the store.
When diagnosing, it is important to take into account the age of the equipment. Older models (from previous years) are characterized by wear and tear on mechanical parts, while new digital models are more likely to experience failures in electronics or sensor errors.Atlant, Biryusa older models) are characterized by wear and tear on mechanical parts, while newer digital models are more likely to experience electronic failures or sensor errors. Sound localization also important: from below (compressor), from behind (relay, capacitor) or inside the chamber (thermostat, fan).
Below is a table that will help classify the problem:
| Sound type | Probable cause | Nature of behavior refrigerator | Required actions |
|---|---|---|---|
| Single loud click when stopping | Thermal expansion of plastic/metal | Cooling is normal, works cyclically | Do nothing not necessary, this is normal |
| Series of frequent clicks, no cooling | Malfunction of the starting relay | The compressor hums for 1-2 seconds and goes silent | Replacing the starting relay |
| Click and turn on the light/fan | Faulty door switch | Light blinks when the door is closed | Adjusting or replacing the door sensor |
| Quiet clicks inside cameras | Operation of dampers (No Frost) or thermostat | Temperature conditions are maintained | Observation, checking settings |
| Metallic clanging at startup | Compressor wear or water hammer | Vibration, possible lack of cold | Urgent call for a technician |
Using this table, you can weed out safe causes and focus on those that require repair. Remember that accurate diagnostics often require opening the technical area, which may affect the warranty.
Practical recommendations and inspection checklist
Before calling a technician, try to perform a number of simple steps. Often the problem is solved without disassembling the unit. The main thing is safety: carry out all manipulations with electrical components only when the device is disconnected from the network. Do not ignore the operating rules specified in the instructions for your model.
Check whether the refrigerator is located too close to the wall or furniture. The gap at the back should be at least 5-10 cm for free air circulation. If the condenser (grid at the back) overheats, it can cause the metal to expand and click, as well as overload the compressor. Level the position of the refrigerator by tightening the front legs.
If you have not defrosted the refrigerator for a long time, do so. Even models with No Frost can become overgrown with ice in hard-to-reach places if the drainage is clogged or the door does not close tightly. Complete defrosting (at least 24 hours with the doors open) will help eliminate ice jams and check whether the sounds disappear.
☑️ Primary diagnosis of noise
⚠️ Attention: Never try to forcefully bend metal tubes condenser or evaporator. They are filled with freon under pressure. Damage to the tube will lead to a gas leak and will require complex, expensive repairs with refilling.
If, after defrosting and checking the installation, the clicks continue, especially if they are intrusive, rhythmic and accompanied by a lack of cold, it is necessary to prepare for repairs. Record the nature of the sound on a voice recorder - this will greatly help the technician during the initial consultation.
Frequently asked questions (FAQ)
Why does the refrigerator click but does not turn on?
Most likely, the starting relay or the compressor itself has failed. The relay tries to start the engine, clicks, but due to a breakdown the circuit opens. Relay replacement or compressor diagnostics is required.
Is it normal for the refrigerator to click after defrosting?
Yes, this is normal. When defrosting, you load warm food, and a sharp temperature change causes thermal expansion of materials (plastic, metal), which is accompanied by cracking and clicking sounds. This should go away in a day.
Can the thermostat click?
Yes, a mechanical thermostat makes a click when the contacts open. This is a regular job. However, if the clicks have become very loud or frequent, the device may need to be replaced.
Is it dangerous to ignore clicks in the refrigerator?
If it is a thermal crackling sound, it is not dangerous. If the relay clicks when you try to start, this is dangerous, as the compressor winding may burn out. It is better not to ignore repeated electrical clicks.
How much does it cost to replace a start relay?
The relay itself is inexpensive (usually from 500 to 1500 rubles, depending on the model), but the work of a technician to replace and diagnose can cost more. In some cases, it is easier and cheaper to call a specialist than to buy parts and tools separately.