The situation when the refrigerator turns on and immediately turns off.is familiar to many owners of household appliances. You hear a characteristic click, the motor begins to hum, but after a few seconds (usually from 5 to 15) the click is heard again and silence falls. At this moment, the light inside the chamber may go out or remain on, but the cold ceases to be produced. This is a classic symptom of engine protection from overload or failure to start.
Such behavior of the unit indicates that the control system or itself compressor cannot reach operating mode. The electric motor tries to start, consumes a huge starting current, but due to a mechanical or electrical obstacle the rotor does not turn. As a result, the thermal relay overheats and breaks the circuit to prevent the windings from burning out. If you ignore this signal, you can completely destroy the expensive motor-compressor.
In this article we will analyze in detail the main reasons why The refrigerator clicks and does not start. We will look at both simple faults that you can fix yourself, and complex breakdowns that require the intervention of a specialist. Understanding the nature of the sound and the cyclic nature of switching on will help you save time and money on diagnostics.
Faults in the start relay and thermal protection
The most common reason why the refrigerator turns on for a few seconds and turns offis the failure of the start protection relay This small black or white box, mounted on the side of the compressor, is responsible for supplying voltage to the starting winding of the engine at the moment of start. Inside it there is a coil or a posistor, which wear out over time.
When the relay breaks, it cannot create the necessary magnetic pulse to shift the rotor. The engine hums, trying to start, but cannot turn over. Thermal protection, built into the same relay or located nearby, detects a sharp increase in current and temperature, opening the contacts. You hear a loud click and the power turns off. After some time, when the bimetallic plate cools down, the cycle repeats.
⚠️ Attention: If you hear a loud metal clanging or cracking sound immediately after the power click, do not try to start the refrigerator repeatedly. This may indicate a wedge in the piston group, and each such start finishes off the compressor.
Diagnostics of the relay often does not require complex equipment. If you have minimal electrical skills, you can remove the relay and shake it near your ear. If the ringing of scattered parts is heard inside or carbon deposits are visible on the contacts, the part must be replaced. It is also important to check the integrity of the wires going to the compressor terminals, since oxidation of the contacts creates additional resistance.
- 🔌 Symptoms: Humming for 5-10 seconds, a loud click, no cold, repeating the cycle after 2-5 minutes.
- 🛠 Solution: Replacing the start relay with similar (it is important that the marking and type of compressor match).
- 💡 Nuance: In modern models with inverter compressors there is no separate starting relay, the problem may be in the control board.
Problems with thermostat and temperature sensors
The second most common cause of unstable operation is a malfunction of thermostat (thermostat) or electronic sensors. In older mechanically controlled models, the thermostat is a capillary tube that responds to changes in temperature in the chamber. If its contacts are stuck or the calibration has gone wrong, it may give a false signal that the desired temperature has already been reached, although in reality it is warm in the refrigerator.
However, if the refrigerator turns on and immediately turns off, the problem more often lies in a short circuit of the thermostat contacts or an open circuit. In this case, the compressor may receive intermittent power. In electronic models, this is achieved by temperature sensors that transmit data to the control module. If the sensor is “lying,” the module can block the start of the compressor or turn it off prematurely.
Checking a mechanical thermostat is simple: you need to short-circuit the two wires going to it, bypassing the device itself. If the compressor starts and works normally, then the problem is in the thermostat.
How to check the electronic sensor?
To check the electronic temperature sensor, you will need a multimeter. It is necessary to measure its resistance at room temperature and compare it with the tabulated values for your model. Often the sensors have a negative TCR, that is, when heated, their resistance drops.
- 🌡 Mechanical thermostat: Checked by checking the contacts, often requires complete replacement.
- 📡 Electronic sensor: Requires a resistance check, may fail due to oxidation of the chip.
- ❄️ Impact on the cycle: A faulty sensor can cause the compressor to work jerkily.
Compressor wedge and mechanical breakdowns
The most unpleasant scenario, explaining why the refrigerator clicks and does not start is a mechanical compressor wedge. Inside the sealed engine casing there are rubbing metal parts: pistons, cylinders, crankshaft. Over time, the oil loses its properties, thickens or burns out, which leads to dry friction and scuffing. At some point, the piston simply gets stuck in the cylinder.
When you try to start, the electric motor creates a powerful magnetic field, the rotor tries to turn, but physically cannot budge. The current in the windings instantly increases significantly. The starting relay is triggered, but cannot start the motor, and the thermal protection emergency cuts off the power. The characteristic sound in this case is a strained hum, turning into silence after a click.
There is a myth that a jammed compressor can be “unwedged” by applying high voltage or an impact. This is a dangerous misconception. Even if it is possible to start such a unit for a short time, it will not work for long, since the geometry of the parts is already broken. The only correct solution in this case is to replace the compressor with a new one, which requires professional sealing of the system and refilling with freon.
| Type of malfunction | Sound at startup | Relay behavior | Probability of repair |
|---|---|---|---|
| The compressor is jammed | Strained hum, hum | Clicks after 5-10 seconds | Replacement of the compressor |
| Winding burned out | Silence or humming | May not click | Replacing the compressor |
| Faulty starter | Silence or slight hum | Frequent clicks | High (relay replacement) |
| Wiring problems | Miscellaneous | Chaotic | High (recovery) |
Faults in the electrical circuit and wiring
Sometimes the reason that the refrigerator turns on and immediately turns offlies not in the unit itself, but in the external electrical network or internal wiring. Poor contact in the socket, the use of extension cables of insufficient cross-section or oxidation of plugs leads to a voltage drop. The compressor does not have enough power to start, the current increases, and the protection turns off the device.
Inside the refrigerator, the wires can rub against the body due to vibration, especially at the points where they enter the compressor or thermostat. If a short circuit occurs to the housing, it is no longer the thermal relay that is triggered, but the circuit breaker in the apartment panel or the RCD. It is important to check the integrity of the insulation of visible sections of the wiring.
It is also worth paying attention to the surge protector or stabilizer, if they are used. Cheap models of stabilizers may have a response threshold that is too narrow or a delay that conflicts with the refrigerator’s startup algorithm. Try to plug the device directly into a working outlet to eliminate this factor.
- 🔌 Socket: Check whether the plug is getting hot and whether it is loose in the socket.
- ⚡ Voltage: Low voltage in the network is a common cause of unsuccessful motor starts.
- 🔗 Contacts: Oxidized terminals on the compressor increase resistance and heating.
Failures in the electronic control module
In modern models No Frost and multi-compartment refrigerators, the electronic control module is responsible for starting the engine. This is the “brain” of the device, which analyzes sensor readings and gives the command to turn on the compressor. If triacs, relays or other elements in the control board are burned out, it can send incorrect signals, which is why the refrigerator turns on and immediately turns off.
Often the module fails due to power surges in the network or moisture (condensation). Symptoms may vary: the refrigerator may not respond to commands at all, hum intermittently, or turn on for a short time. Diagnostics of the module requires special knowledge and equipment, since it is necessary to ring tracks and radio components.
⚠️ Attention: Repairing an electronic module at home is only possible if you have experience working with a soldering iron and circuits. In most cases, it is cheaper and more reliable to replace the entire board with an original one or a high-quality analogue.
If you notice that along with startup problems error codes appear on the display (for example, F1, E2, etc.), this is a direct indication of a faulty electronics or sensors. The decoding of the code should be found in the instructions for your specific model LG, Samsung, Indesit or another brand.
☑️ Primary diagnostics before calling a technician
Diagnostics and troubleshooting methods
To understand exactly why the refrigerator clicks and does not startit is necessary to carry out consistent diagnostics. Start with a visual inspection: if there are any melts on the wires, if there is a smell of burnt insulation. Then listen to the character of the sound. A steady hum followed by a click indicates a start relay or wedge. No sound at all - there is an open circuit or a module.
If you decide to check the start relay yourself, be sure to unplug the refrigerator! Remove the back cover, disconnect the relay from the compressor. Visually assess the condition of the contacts: they should be clean, without carbon deposits or melting. If the relay is a posistor, check its resistance - it should be within the normal range (usually several tens of ohms).
In cases where self-diagnosis does not produce results, or you find complex faults (burning smell, traces of oil under the refrigerator, swollen compressor), it is better to turn to professionals. Repairing the cooling system requires evacuation and charging with refrigerant, which cannot be done without special equipment.
Frequently asked questions (FAQ)
Is it possible to operate a refrigerator if it turns on and turns off immediately?
It is absolutely not possible. Long-term operation in this mode leads to overheating of the compressor windings, burnout of the starting relay and, ultimately, to complete jamming of the motor. This will turn a simple repair into an expensive compressor replacement.
How much does it cost to replace the start relay?
The cost of the part itself is usually low and depends on the model of the refrigerator. However, the price consists of the cost of calling a technician and replacement work. On average, repairs involving the replacement of a relay are much cheaper than replacing a compressor.
Why does the refrigerator hum but does not start after defrosting?
If the problem appeared after defrosting, moisture may have gotten into the electrical contacts or into the start relay. Allow the device to dry completely for several hours. If the problem persists, it is likely a coincidence with the failure of the relay or thermostat.
Can low voltage in the network cause a shutdown?
Yes, if the voltage in the network drops below 190-200 Volts, the engine power may not be enough to overcome the pressure in the system. The compressor hums, does not start, heats up and is switched off by protection. In such cases, a voltage stabilizer is needed.