The situation when your favorite refrigerator makes a characteristic click, but the long-awaited hum of the motor is not heard, can cause panic in any home cook. This sound usually indicates that the unit is trying to start, but for a number of technical reasons the operating cycle is interrupted at the start. Ignoring such symptoms can lead to damage to products and more expensive repairs in the future.
Before calling the service center, it is worth conducting initial diagnostics yourself, since in 30% of cases the problem lies in basic things that do not require the intervention of a specialist. Click - this is a signal that the electrical circuit is closed, but further process is blocked by protection or the lack of necessary parameters to start.
In this article we will analyze in detail the mechanics of the process, list the main components that fail, and offer a step-by-step algorithm of actions. Understanding how the compressor works will help you make an informed decision about the advisability of repairing or replacing parts. start-protection relay and compressor, will help you make an informed decision about the advisability of repair or replacement of parts.
The principle of operation of the starting mechanism and the nature of the click
To understand why the unit does not start, you need to understand physics of the process. When voltage is applied to the motor windings, an electromagnetic field appears, which should move the piston group from its place. The click you hear most often comes from starting relay or a thermal protection relay.
At the moment of switching on, the current in the windings increases sharply, creating a magnetic flux. If the engine does not start within a split second, the protection is activated, breaking the circuit - hence the sound. This is a normal reaction of the system to the impossibility of starting, be it the motor jamming or the absence of a starting impulse.
⚠️ Attention: Frequent attempts to turn on (clicking every 10-20 seconds) can quickly damage the motor windings due to overheating. If you hear a series of clicks, immediately unplug the device.
There are two main types of relays: electromagnetic (old models) and posistor (modern). In the first, the current passes through the coil, which draws in the core and closes the starting winding. Secondly, the current heats a special ceramic element (posistor), which changes its resistance and opens the circuit after starting. It is the failure of the posistor that is the most common cause of clicking in modern refrigerators.
Main causes of malfunction: from relay to compressor
Diagnostics begins with eliminating the most probable and easy-to-eliminate causes. The problem does not always lie deep inside the metal casing of the motor. External factors or easily replaceable controls are often to blame.
Let's consider the main components, the failure of which causes the described symptoms. It is important to understand that compressor is the heart of the refrigerator, and if it "knocks" or hums when you try to start, but does not spin, this may indicate a mechanical wedge.
- 🔌 Starting relay: The most common culprit. The contacts inside could burn out, and the posistor could lose its properties, ceasing to pass current to the starting winding.
- ⚡ Thermoregulator: If the temperature sensor is “stuck” or faulty, it may not send a signal to turn on the motor, or, conversely, constantly try to start it.
- 🔥 Thermal protection relay: This element is designed to break the circuit when overheated. If it is faulty, it can open the circuit instantly, preventing the engine from even trying to turn over.
- 🔩 Compressor jamming: Mechanical failure in which the pistons get stuck in the cylinder. The motor hums, clicks, but the shaft does not rotate.
It is also worth considering the condition of the wiring. Oxidized contacts or broken wires can create high resistance, due to which the voltage is not enough to start, but enough to trigger the relay electromagnet.
Diagnostics of the starting relay and thermostat
If you decide to test it yourself, start with a visual inspection and testing with a multimeter. To do this, you will need to remove the back panel of the refrigerator and gain access to the compressor compartment. Safety —above all: all work is carried out only when the device is disconnected from the network.
Remove the starting relay from the compressor contacts. It is usually secured with latches or screws. Carefully inspect the housing for melting, cracks or traces of burning. If the relay is electromagnetic, you can shake it near your ear: if a knock is heard inside, it means the mechanism is destroyed.
To check a posistor relay, you will need a multimeter in resistance measurement mode. Connect the probes to the contacts. At room temperature, the resistance should be within normal limits (usually several tens of ohms). If the device shows infinity or zero, the part requires replacement.
How to check the thermostat?
Disconnect the wires from the thermostat and short them together. If the refrigerator turns on and works, it means the temperature sensor is faulty and needs to be replaced.
The temperature regulator is checked in the same way. Depending on the design, its contacts should close when the temperature rises. If the circuit does not close, the motor will not receive a start command. Replacing these elements is an inexpensive procedure and can often be done at home.
Checking the compressor and electrical circuit
If the relay and thermostat are working, attention turns to the engine itself. The compressor has three terminals: common, starting and working. It is necessary to “ring” the windings with a multimeter. There must be a certain resistance between the terminals (usually from 10 to 30 ohms). If the resistance is infinitely high, the winding is broken; if it is close to zero, there is an interturn short circuit.
Pay special attention to checking for breakdown on the housing. One probe of the multimeter is pressed against any contact, the second - against a copper tube or an unpainted part of the case. The device should show infinity. The presence of resistance indicates that it is going to ground, which is life-threatening. Electric motor data-i="96">Difficulty of repair electric motor breaks through to ground, which is life-threatening.
| Symptom | Probable Cause | Character of sound | Difficulty of repair |
|---|---|---|---|
| Single click, silence | Faulty start relay | Clear click, no buzz | Low |
| Click and buzz for 3-5 seconds | Compressor jammed | Strained hum, then click | High (replacement) |
| Series of frequent clicks | Thermal protection has activated | Quiet frequent clicks | Medium |
| Click and immediately the light goes out | Short circuit in circuit | Loud crackling | High |
It is important to note that if the compressor has good resistance but does not start, it may not have enough starting torque. In old models, capacitors were used for this, in new ones - electronics. Checking the power circuit also includes inspecting the wires for damage by rodents or melting.
☑️ Diagnostics before calling a technician
The mechanical wedge of the compressor: can it be saved?
The most unpleasant situation is when the electrical part is working properly, but the motor physically cannot turn over. This is called wedge. This happens due to the production of rubbing steam, chips getting into the cylinder or thickened oil. In this case, the refrigerator clicks, trying to overcome the resistance, but the shaft stands still.
There is a folk method of “resuscitation” that sometimes helps, but you should only use it if you understand the risks. The essence of the method is to apply increased voltage to the starting winding, bypassing the standard circuit, in order to create a powerful jerk. However, this can completely finish off the motor or lead to a fire.
⚠️ Attention: Trying to wedge the compressor by supplying 220V directly to the starting winding is dangerous! Use only special devices (UPZK) and strictly follow safety precautions. If you are not an electrician, don’t take risks.
If the compressor is jammed, it most often needs to be replaced. Repairing the unit itself (opening, replacing the piston group) is not economically feasible and requires industrial equipment for evacuation and refilling with freon.
When you need to call a professional technician
Despite the desire to save money, there are situations when independent repair is impossible or dangerous. If diagnostics show that the problem is in a sealed circuit, freon leakage or mechanical destruction of the compressor, you cannot do without a specialist.
A specialist is also needed if, after replacing the relay, the refrigerator began to work, but after a while the situation repeated itself. This may indicate deeper problems in the control system or unstable voltage in the network, which requires the installation of a stabilizer.
Professional repair includes not only replacing the part, but also checking the system for leaks, evacuating the circuit and charging with refrigerant in a strictly defined amount. Violation of the refueling technology will lead to rapid breakdown of the new compressor.
Prevention and operating rules
To extend the life of the refrigerator and avoid a situation where it clicks but does not turn on, Follow simple operating rules. First of all, ensure adequate ventilation of the rear wall. If the condenser (black grille at the back) is covered with dust, the heat transfer efficiency drops, the motor overheats and the thermal protection is triggered more often.
Do not place the refrigerator close to the wall, leave a gap of at least 10 cm. Also avoid frequently opening the door and loading warm food, which forces the compressor to work at its limit.
Regularly check the rubber seals on the doors. If they do not fit tightly, warm air enters the chamber, the temperature rises, and the motor is forced to turn on more often, which reduces its resource. Timely defrosting Also important: the layer of ice acts as a heat insulator, forcing the equipment to work more intensely.
Why does the refrigerator click immediately after defrosting?
If after defrosting the refrigerator begins to click and does not turn on, moisture may have gotten on the electrical contacts or in the start relay. Allow the appliance to dry completely for 4-6 hours when turned off before turning it on again.
Is it possible to use the refrigerator if it clicks but freezes?
The unit can work in this mode, but this is an emergency mode. Clicking sounds indicate overload or malfunction of the starting equipment. Sooner or later the motor will burn out or the machine in the apartment will break. It is better to eliminate the cause of the noise.
How much does it cost to replace the start relay?
The part itself is inexpensive (from 500 to 2000 rubles, depending on the model). However, if you do not have the skills, you will have to pay for the work of the master. In total, this is much cheaper than replacing the compressor.
Does a voltage surge affect the appearance of clicks?
Yes, sudden surges in voltage in the network can damage the starting relay or motor windings. If the lights in your house flicker frequently, it is recommended to connect the refrigerator through a voltage stabilizer or surge protector with protection.