The appearance of extraneous sounds in the operation of household appliances always causes alarm, especially if it refrigeration unitis responsible for the safety products. The situation when the device makes a characteristic click at the time of startup or immediately after shutdown is one of the most common complaints from users. In most cases, this sound indicates the normal operation of the automation, however, there are scenarios that indicate an incipient malfunction.
Understanding the physics of the processes occurring inside the motor-compressor allows us to distinguish normality from pathology. A short, single click usually means the thermostat is activated, which is a necessary condition for starting the engine. However, if the sound is repeated cyclically, accompanied by a buzzing or crackling sound, the signal cannot be ignored. Next, we will analyze in detail the mechanics of noise occurrence and action algorithms. start relay or thermostat, which is a necessary condition for starting the engine. However, if the sound is repeated cyclically, accompanied by a buzzing or crackling sound, the signal cannot be ignored. Next, we will analyze in detail the mechanics of noise generation and action algorithms.
Normal operation of the thermostat and start relay
The main source of sounds in the refrigerator is the compressor control system. The thermostat constantly monitors the temperature inside the chambers. As soon as it rises above the set threshold, the thermostat contacts close and you hear a distinct click. This is a signal that the circuit is closed and voltage is applied to the start relay.
In turn, the start relay performs a critical function: it briefly connects the motor starting winding to create rotor torque. It is at this moment that the second click occurs, followed by the hum of the compressor starting up. In a working unit, this process takes a split second and should not cause concern.
- 🔊 A single click before the start of the hum is a sign that the thermostat contacts are closing.
- ⚡ The second click after 1-2 seconds is the activation of the relay trigger.
- ❄️ Sound when stopping motor - opening the contacts and equalizing the freon pressure.
It is important to note that modern inverter models work differently. They do not have a hard switch on and off, so the characteristic clicks may be completely absent or barely audible. If you have a classic model Indesit, Atlant or Beko, then the sound of the switching cycles is a normal situation.
Symptoms of a faulty start relay
The situation changes dramatically if the clicks become frequent and rhythmic, and The compressor still does not start. This is a classic symptom of a malfunction start-up protection relay. The device tries to start the motor, a click is heard, but due to overcurrent or mechanical sticking of the contacts, the protection is triggered and the circuit opens. After some time, the cycle repeats.
A common reason for this behavior is wear of the bimetallic plate inside the relay or burning of the contacts. Also, the problem may lie in the compressor itself, which, due to exhaustion of its resource, consumes too much starting current, causing the relay to “snap off” ahead of time. Long-term operation in this mode can lead to overheating of the motor windings.
⚠️ Attention: If you hear a series of clicks with an interval of 1-2 minutes, and the refrigerator is not cooling, immediately disconnect the device from the network. Continuing to operate in constant start-up mode may (burn) the compressor windings.
The relay can be diagnosed visually by removing the back cover of the unit. There should be no traces of burning, melted plastic or the characteristic smell of burnt insulation on the device. However, only checking with a multimeter or replacing it with a known-good analogue will give an accurate answer.
Is it possible to temporarily remove the relay?
Theoretically, some technicians close the contacts to test the compressor, but doing this is strictly not recommended without skills. You can damage the wiring or get an electric shock, since there is a high voltage of 220V at the contacts.
Problems with the compressor and water hammer
A more serious problem is the malfunction of the very heart of the refrigerator - compressor. If the piston group is worn out or there is excess pressure in the system, starting the engine may be accompanied by a loud, metallic click or even a knocking sound. This often occurs due to the so-called water hammer, when liquid freon or oil enters the cylinder at the moment when the valve should be closed.
Another reason is a break or burnout of the internal wiring, or jamming of the engine shaft. In this case, you may hear a powerful clicking and humming noise that ends abruptly. Attempting repeated launches in such a situation is useless and dangerous. It is also worth checking the mounting of the motor to the frame: if the bolts are loose, vibration at start will cause clanging and impacts on the body.
| Sound type | Probable cause | Required actions |
|---|---|---|
| Quiet, single click | Normal operation of the thermostat | Observation, no repair required |
| Series of clicks, the motor hums, but does not start | Faulty starting relay | Replacement of the relay (budget repair) |
| Loud metallic clanging at start | Compressor wear or water hammer | Master diagnostics, compressor replacement possible |
| Crackling and clicking inside the chamber | Thermal expansion of plastic/tubes | The norm for new refrigerators or after defrosting |
The cost of replacing a compressor is high and is often comparable to the price of a new budget refrigerator. Therefore, if diagnostics have confirmed the death of the motor, it makes sense to evaluate the economic feasibility of repairs. In models LG and Samsung with linear compressors, the situation may be different, since there are fewer moving parts, but diagnostics are more difficult.
The influence of voltage drops in the network
Unstable power supply is the scourge of many residential areas. If the network voltage drops below the permissible minimum (usually below 190-200 Volts), the starting torque may not be enough to rotate the compressor shaft. In this case, the relay will click, trying to start the engine, but the protection will stop it.
A similar situation occurs during voltage surges. Modern refrigerators are equipped with built-in protection that blocks startup for a certain time (usually 3-10 minutes) after a surge. During this period, you may hear the click of the timer or protection relay, after which there is silence. This is a normal reaction of electronics that protects equipment from combustion.
- 📉 Low voltage: the relay clicks, the motor hums and does not start.
- 🌩️ Voltage surge: a temporary switching lock is triggered.
- 🔌 Poor contact in socket: sparking and clicking at the plug connection point.
To solve the problem, it is recommended to check the voltage in the network with a multimeter or use a stabilizer. It is also worth inspecting the socket: if it is old and loose, the contact may be unstable, which causes sparking and characteristic sounds when a load is applied.
☑️ Checking the power supply
Thermal expansion of housing materials
Do not forget about the physical properties of materials. The inner walls of the refrigerator, plastic containers and metal evaporator tubes expand or contract as the temperature changes. This process, called thermal expansion, is often accompanied by crackling sounds, clicks, or even sounds reminiscent of gunshots.
Such sounds are especially common in new refrigerators or immediately after complete defrosting (defrosting). When you turn on an empty unit, the sudden temperature change causes the materials to “play.” Usually these sounds are localized inside the camera and are not associated with the operation of the motor.
Over time, when the temperature stabilizes, the frequency of such clicks should decrease. If the cracking becomes constant and loud, the geometry of the housing may be broken or the evaporator is installed incorrectly, which, when expanding, touches other structural elements.
⚠️ Attention: If clicks inside the chamber are accompanied by the appearance of ice in one place or insufficient cooling, this may indicate a freon leak or a malfunction of the No Frost system. In this case, you need to call a specialist.
Diagnostics and user procedure
If suspicious sounds appear, do not panic. You can carry out the initial diagnosis yourself, following safety precautions. The first thing to do is to determine the nature of the sound and its frequency. If the refrigerator works normally and cools, and a click is heard once every 30-40 minutes when turned on, most likely, everything is in order with the equipment.
If you observe a series of clicks, lack of cold or heating of the rear grille, you need to follow the algorithm. Unplug the device and let it stand for 15-20 minutes to equalize the pressure and cool down the protection. Then turn it on again and listen.
For a deeper check, you will need access to the compressor compartment (usually at the bottom rear). By removing the protective cover, you can visually assess the condition of the relay and wiring. However, remember: any manipulations with the electrical part must be carried out with the power completely turned off.
If the problem is not solved by simply rebooting or replacing the relay (if you know how to do this), you need to contact a service center. Professional diagnostics using pressure gauges and testers will allow you to accurately determine the cause and cost of restoration.
Why does the refrigerator click but does not turn on after defrosting?
After defrosting, a lot of moisture could remain in the system, or the balance of freon pressure could be disrupted. It is also possible that the thermostat is not sensing the correct temperature due to residual cold. Let the refrigerator stand off for several hours, then turn it back on. If the clicking continues, the problem is in the relay or compressor.
Is it dangerous if a new refrigerator clicks?
In the first days of operation, a new refrigerator may make various sounds, including clicks. This involves grinding in the parts, expanding the plastic, and adjusting the automation. If the sound does not turn into a constant knocking or crackling sound, and there is cold inside, there is nothing to worry about.
Is it possible to use a refrigerator if it constantly clicks?
Operating equipment in this mode is extremely undesirable. Constant starts without reaching operating mode wear out the motor windings and can lead to a fire hazard or final failure of the compressor. It is better to turn off the device until the reasons are determined.
How much does it cost to replace the starting relay?
The relay itself is inexpensive (from 500 to 2000 rubles, depending on the model and brand). However, the cost of an on-call technician will consist of diagnostics, on-site visits and replacement. As a result, repairs can cost 3000-5000 rubles, which is much cheaper than replacing the compressor.