The appearance of extraneous sounds in household appliances often becomes an alarm signal for the owner. If your the refrigerator began to click, this does not always mean a critical breakdown requiring an immediate call to the repairman. In some cases, periodic clicks are part of the compressor's normal operation algorithm, especially in models with a system No Frost or digital control. However, a sudden change in the sound background cannot be ignored, as this may indicate wear of the start relay or problems with the electrical circuit.
The specificity of sound diagnostics is that the nature of the click can differ radically depending on the source of vibration. The mechanical knock that occurs when the engine starts is often confused with the electrical clicks of the thermostat. Understanding this difference allows you to save significant money on diagnostics. In this article, we will analyze in detail the physics of the processes that cause noise and determine when equipment needs urgent intervention.
⚠️ Attention: Before carrying out any diagnostic work or replacing parts, be sure to disconnect the refrigeration equipment from the power supply. Working with live electrical components is deadly.
The mechanism of operation of the compressor and start relay
The main source of sound in the refrigerator is compressor, which works on the principle of refrigerant compression. To start this powerful electric motor, a special device is used - a starting relay. It is this that supplies the necessary current pulse to the motor windings. When the compressor is turned on or off, the contacts inside the relay open or close, which is physically accompanied by a characteristic click.
If the refrigerator clicks once when starting and once when stopping, this is absolutely normal. The relay design involves mechanical movement of a core or bimetallic strip. However, if you hear a series of rapid clicking noises that are not followed by the engine starting, the situation requires attention. This may indicate that the relay is trying to start the engine, but cannot do this due to low voltage or internal defects.
A critical sign of a malfunction is a situation when a loud click is heard, the motor hums for 2-3 seconds, then clicks again and goes silent. This cycle can be repeated endlessly, which indicates a jammed compressor or failure of the starting winding. In this case, further attempts to turn on may lead to burnout of the wiring.- 🔊 Single click —normal operation of the thermostat or relay when the set value is reached temperature.
- 🔊 A series of clicks without starting —an attempt by the relay to start a blocked or faulty compressor.
- 🔊 Quiet periodic clicks —can be emitted by the system dampers No Frost when adjusting flows air.
Thermal expansion of housing and evaporator materials
One of the most common and least dangerous reasons for the appearance of sounds is the physical process of thermal expansion. The inner walls of the refrigerator compartment, plastic trays and metal evaporator are constantly exposed to temperature changes. When cooled, materials contract; when heated (during the compressor is idle), they expand. This process is often accompanied by a crashing sound, reminiscent of clicks or even shots.
This effect is especially noticeable in new refrigerators or after defrosting. Plastic that has not yet gone through the full shrink cycle may respond more loudly to temperature changes. Also, the source of sound can be a layer of ice on the evaporator, which cracks when the operating mode of the unit changes. Typically, such sounds do not pose any threat to the functionality of the device.
If the clicks become intrusive and loud, it is worth checking whether there are any foreign objects adjacent to the case. Vibration from the compressor can be transmitted to nearby bottles or plates, creating the illusion that the refrigerator itself is malfunctioning. Make sure that the equipment is installed level and does not touch walls or furniture.
- 🌡️ Cyclic nature —sounds appear mainly immediately after the compressor is turned off or before it is turned on.
- 🌡️ Depending on temperature —the greater the temperature difference between inside and outside the chamber, the more intense the cracking can be.
- 🌡️ No other symptoms —the temperature in the chambers remains stable, the food does not spoil.
Why does the new refrigerator click louder?
New models use modern, more rigid types of plastic and insulating materials. During initial operation, they go through a stage of “grinding in” and adaptation to temperature conditions, which may be accompanied by more pronounced sounds of thermal expansion, which subside over time.
Faults in the start-up protection relay and thermostat
When the refrigerator clicks but does not turn on, the start-up protection relay becomes the first suspect. This small unit, mounted on the compressor, is responsible for supplying voltage. Over time, the contacts inside the relay oxidize or burn, resulting in a poor connection. When we try to start, sparking occurs, which we hear as a click, but the current does not flow to the motor windings in full.
A similar situation can be observed with thermostat (thermostat). If its contacts are stuck or the mechanism is worn out, it may constantly “search” for the switching point, making frequent clicking sounds. In electronic models, this function is performed by the control module, and clicks in this case can be produced by solenoid valves or relays on the board.
Diagnosing the relay often requires its dismantling and visual inspection. There should be no traces of burning or melting on the plastic. If the relay emits a burning smell when operating, it must be replaced. Operating a refrigerator with a faulty relay is dangerous because the compressor may burn out due to operation in the start-stop mode.
⚠️ Attention: Start relays come in different types and are only suitable for specific compressor models. Installing the wrong relay can result in immediate engine failure. Check the labeling with the original product.
Problems with the fan in the No Frost system
In refrigerators with the system No Frost fans are responsible for circulating cold air. If the fan blades are contaminated with dust or ice has frozen on them, a characteristic cracking or knocking noise may occur, which can easily be confused with electrical clicks. A rotating fan can touch ice or a foreign object that has gotten into the air duct.
Often the problem lies in the wear of the fan bearings. When the lubricant dries, the shaft begins to rotate with difficulty, making intermittent sounds. On some models, the fan only turns on when the door is open or on a timer, so diagnostics may be difficult. To check the source of the sound, you can carefully remove the back panel in the freezer (after defrosting the refrigerator).
If the fan is damaged, it must be replaced. Operating the system with a non-working or noisy fan will result in the cold no longer being evenly distributed throughout the chambers. As a result, there will be a block of ice in one corner, and in the other, the food will begin to deteriorate.
- ❄️ Sound localization —the noise comes from the depths of the freezer compartment or from behind the back wall.
- ❄️ Dependence on the cycle —sounds can only appear during defrosting or active cooling.
- ❄️ Change in tone —when you press the door (in some models the fan turns off), the sound may disappear.
☑️ Fan diagnostics
Deformation and wear of the compressor
The most alarming symptom is when clicks come directly from the compressor housing. This may indicate mechanical destruction of internal components: valves, piston group or engine suspension. If the compressor “knocks” when starting, this often means that it is working at the limit of its capabilities or has already exhausted its service life.
In some cases, the cause is loosening of the mounting bolts or shock absorbers on which the motor-compressor is suspended. Vibration is transmitted to the metal casing, causing resonance and impacts on the walls of the casing. You can check the fastening yourself by slightly shaking the compressor (only with the device turned off and cooled down!). If the motor is loose, it needs to be secured.
However, if a metallic clanging sound is heard inside the compressor “pot” itself, repairs are not economically feasible. Replacing a compressor is a complex procedure that requires evacuation of the system and refilling with freon. Often the cost of such repairs is comparable to the purchase of a new refrigerator.
| Symptom | Probable cause | Difficulty of repair | Risk for equipment |
|---|---|---|---|
| Single click at start | Normal (relay operation) | Not required | Absent |
| Frequent clicks, the motor does not start | Malfunction of the starting relay | Low | High (motor combustion) |
| Crackling inside the chamber | Thermal expansion | Not required | Absent |
| Humming with periodic blows | Compressor wear | High (replacement) | Critical |
When you need to call a technician: critical signs
There are a number of signs in which independent experiments should be stopped and you should turn to professionals. If, after defrosting and checking the voltage in the network, the refrigerator continues to make alarming sounds, and the temperature in the chambers does not drop, the problem is deeper than it seems. The technician will measure the starting winding current and pressure in the system, which cannot be done without special equipment.
It is especially dangerous to ignore the smell of burnt insulation or plastic. If thick smoke or a distinct burning smell is added to the clicking sounds, this is a direct indication of a short circuit in the wiring or motor windings. In such a situation, minutes may count until a fire breaks out.
Also, the help of a specialist is needed if the refrigerant needs to be replaced or pipes soldered. These works require a license and special tools. An attempt to solder the tube yourself often leads to moisture getting into the system, which will put the new compressor out of action in a few months.
- 🛠️ Burning smell - any smell of burnt wiring requires immediate shutdown.
- 🛠️ Lack of cold - if the motor is running (or clicking), but there is no cold for more than 6 hours.
- 🛠️ Knocking out plugs —if, when you try to turn on the refrigerator, the circuit breakers in the control panel are triggered.
Can the refrigerator click due to power surges?
Yes, unstable network voltage is a common cause of problems. If the voltage drops below 190V or above 240V, the start relay may not operate correctly, making a clicking noise but not starting the compressor. In regions with an unstable network, it is recommended to use a voltage stabilizer.
Is it normal if the refrigerator clicks immediately after defrosting?
In the first hours after turning on a defrosted refrigerator, clicks may be more frequent. This is due to the fact that the thermostat actively regulates the temperature, and there is still some residual moisture in the system that can crystallize and crack. If after a day the sound does not subside, this is a cause for concern.
Why does the refrigerator click when the door is opened?
A click when opening the door is usually associated with the operation of the light button or the door opening sensor. In some models with the system No Frost at this moment the cold air supply damper may close, which is also accompanied by sound. This is a normal situation.
Does the installation level affect the appearance of clicks?
Yes, if the refrigerator is not level, the vibration from the compressor increases and is transmitted to the housing, causing rattling and knocking. Adjusting the legs of the refrigerator using a building level often helps eliminate extraneous sounds without repair.
What to do if the relay clicks, but the compressor is cold?
If the relay clicks, but the compressor remains cold and does not vibrate, it means that the electrical impulse does not reach it or the motor winding is broken. It is necessary to ring the compressor windings and check the integrity of the supply wires. Most likely, you will need to replace the relay or compressor.