The situation when the refrigerator suddenly stops freezing, and instead of the usual smooth hum you hear only short clicks, always takes you by surprise. This is an alarming signal indicating that trigger mechanism tries to start the engine, but is unsuccessful. In most cases, the problem lies in the electrical circuit or mechanical wear of parts that require immediate attention. Ignoring these sounds can lead to complete failure of an expensive unit, so it is important to quickly determine the source of the noise.
Often equipment owners notice that when they try to start, a characteristic click is heard, after which there is silence, and after a while the cycle repeats. This behavior indicates that the protection system is working, preventing overheating of the windings or more serious damage. Understanding the physics of the process helps not to panic, but to approach diagnosis competently. In this material we will analyze in detail the main causes of malfunctions and methods for eliminating them. compressor makes an attempt to start, a characteristic click is heard, after which there is silence, and after a while the cycle repeats. This behavior indicates that the protection system is working, preventing overheating of the windings or more serious damage. Understanding the physics of the process helps not to panic, but to approach diagnosis competently. In this material we will analyze in detail the main causes of malfunctions and methods for eliminating them.
It is important to note that the nature of the clicks may vary depending on the model of the refrigerator and the type of engine installed. Modern inverter systems behave differently than classic linear compressors. If clicks are accompanied by a lack of cold in the chambers, operation of the device should be stopped immediately to avoid a fire. Further analysis will help you understand whether you can deal with the problem yourself or you will need to call a specialist.
Principle of operation starting relay and compressor
To understand the nature of the sound, you need to understand the structure of the refrigeration unit. The heart of the system is compressorwhich pumps the refrigerant, creating pressure. However, the compressor electric motor itself cannot simply turn on, it requires a push. This function is performed by a starting relay, which supplies a short-term pulse to the starting winding.
When turned on, the relay makes the same click that you hear. If the engine starts successfully, the relay remains in the operating position and the compressor hums smoothly. If startup does not occur, the thermal relay opens the circuit, making a second click, and turns off the power. This cycle can be repeated endlessly until you disconnect the device from the network.
There are several types of relays, and the nature of the sound depends on their design:
- ⚡ Electromagnetic relays: they produce a loud, ringing click when the contacts are closed.
- 🔥 Thermal relays: can produce a quieter, dull sound when the bimetallic plate cools.
- ⏱ Posistor relays: modern analogues that operate almost silently, but can also give sound signals if they break down.
⚠️ Attention: Frequent clicks mean that the compressor is operating in start-stop mode. This leads to rapid overheating of the windings and can cause an interturn short circuit, after which the motor will burn out completely.
Understanding exactly how it should work starting mechanismallows you to distinguish a normal operating sound from a sign of a breakdown. In a working refrigerator, a click is heard only once every few hours - when it is turned on. If you hear a series of clicks every few minutes or seconds, this is a clear sign of a malfunction.
The main reasons for frequent clicks when starting
The most common reason why the compressor clicks is the failure of the starting relay. This is a small plastic block that fits over the motor contacts. Inside it is a coil or posistor, which wears out, oxidizes or burns over time. As a result, the relay cannot keep the contacts closed, and the engine stalls immediately after trying to start.
The second most common reason is the jamming of the piston group of the compressor itself. If a plug of thickened oil has formed inside the mechanism or mechanical failure of parts has occurred, the engine rotor cannot turn. It hums, tries to move, the click of the protection is heard, and the process stops. In this case starting the engine it is physically impossible without major repairs or replacement of the unit.
It is also worth paying attention to the condition of the wiring and contacts:
- 🔌 Oxidation of contacts: carbon deposits on the terminals of the relay or motor prevent the normal flow of current.
- 📉 Low voltage in the network: if the voltage in your outlet drops below 190-200 Volts, the engine does not have enough power to start.
- 🌡 Overheating: if the refrigerator is standing close to the wall or in the sun, the thermal relay may trip prematurely (premature).
Diagnostics should begin with a visual inspection and voltage check. Sometimes the problem is solved by replacing a cheap part, but if the motor itself burns out, the costs will be significant. It is important not to confuse the symptoms: a buzz without a click and clicks without a buzz are different malfunctions.
Diagnostics of a faulty starting relay
If you decide to carry out diagnostics yourself, the first object of your attention should be the starting relay. It is usually located at the bottom of the refrigerator, at the back, next to the compressor. To access it you will need to remove the protective cover and disconnect the wires. Be careful: before starting any work, be sure to disconnect the refrigerator from the power supply.
Remove the relay from its seat. It can be held on by spring brackets or screws. Visually inspect the case: if traces of burning, melting or cracks are visible on the plastic, the part definitely requires replacement. Even if the relay is externally intact, a posistor could burn out inside or the electromagnet core could burn out.
Checking the functionality is carried out using a multimeter:
- Set the multimeter to the continuity mode.
- Check the integrity of the windings (if the relay electromagnetic).
- Shake the relay: if something is loose inside, it means the mechanism is destroyed.
The cost of a new relay is usually low, and it is often easier to buy a new part that matches the markings than to repair the old one. The marking is applied to the body or indicated in the instructions for the refrigerator. When purchasing, pay attention to the type of compressor (linear or inverter), since the relays for them are not interchangeable.
☑️ Checking the start relay
⚠️ Attention: Never try to start the compressor directly, bypassing the relay, unless you are qualified electrician This can lead to a short circuit and electric shock.
Problems with windings and inter-turn short circuits
A more serious problem causing clicking noises is damage to the compressor motor windings. During operation, especially with frequent power surges or overheating, the insulation of the wires may be destroyed. This leads to turn-to-turn short circuitwhen the current begins to flow along a short path, bypassing part of the turns.
With such a defect, the motor consumes a huge current, which instantly triggers the thermal relay. You hear a power-on click, a short hum (or even a burning smell), and then a power-off click again. You can check the windings with a multimeter by measuring the resistance between the contacts. Normal values are usually from 10 to 30 Ohms for the starting winding and a little less for the working winding.
Symptoms of interturn short circuit:
- 🔥 Burning smell: during operation, you can feel the smell of burnt insulation.
- 📉 Low resistance: the multimeter shows values close to zero.
- 🔌 Knocking out plugs: when started, the machine in the apartment panel can be triggered.
If a winding short circuit is diagnosed, repairing the compressor at home is impossible. The entire unit needs to be replaced with a new one. Attempts to rewind the engine in a workshop often turn out to be economically unfeasible and do not guarantee durability.
Mechanical wear and jamming of the compressor
Sometimes the electrical part is working, the relay is new, but the clicking continues. This is a sure sign of a mechanical failure inside the HDA. The piston group of the compressor operates under high pressure, and over time the parts wear out. Cylinder scuffing, valve failure, or bearing displacement may occur.
In this condition, the engine shaft cannot turn. It hits an obstacle, hums, trying to overcome the resistance, but the protection relay turns off the power. The characteristic sound in this case is a strained buzz that turns into a click. Sometimes you can hear a metallic clanging or knocking sound inside the case.
Comparison of symptoms of mechanical and electrical faults:
| Symptom | Electrical fault | Mechanical fault |
|---|---|---|
| Sound at startup | Clicking, silence | Humming, clicking, possible knocking |
| Case heating | Moderate | Strong, fast heating |
| Winding resistance | Normal or break | Often normal |
| Solution | Replacement relay/wiring | Replacing the compressor |
It is more difficult to diagnose the mechanics, since the compressor is sealed. Craftsmen often use the method of “tapping” a hammer on the body of a working (or trying to work) unit. Sometimes this helps to remove a jammed piston, but this is a temporary measure. If the compressor is jammed, its resource is exhausted.
Is it possible to revive a jammed compressor?
There is a method of increasing the starting voltage or using a large capacitor to create a powerful starting pulse. However, this is a risky procedure that can completely kill the engine. At home, it is safer to replace the unit.
The influence of voltage drops and external factors
Do not discount external factors. The quality of electricity in our networks often leaves much to be desired. Power surges can damage sensitive electronics and refrigerator starters. If the lights in your home flicker frequently or the voltage is unstable, the compressor will have difficulty starting.
To protect equipment, it is recommended to use voltage stabilizers. They equalize the network parameters and ensure a smooth engine start. It is also worth checking the outlet that the refrigerator is plugged into. Poor contact in the connector can cause sparking and characteristic clicks, which can be mistaken for the sound of a relay.
Temperature also plays a role. If the refrigerator is located next to a radiator or in direct sunlight, the thermal relay may operate prematurely, preventing the compressor from reaching operating mode. Ensure adequate ventilation of the rear wall of the unit.
Check whether the electrical network in the apartment is overloaded. If powerful consumers (welding, powerful power tools) are working simultaneously with the refrigerator, the voltage may drop to critical values. In such conditions starting current the compressor is insufficient to rotate the rotor.
When it is necessary to call a technician and replace the unit
Independent repair is only possible if the starting relay is replaced or the wiring is checked. If the problem lies in the compressor itself (jamming, burnt out windings), professional intervention is required. The master has the necessary tools for filling with freonsoldering tubes and vacuuming the system.
Replacing a compressor is a labor-intensive process. It includes:
- Draining the old refrigerant and oil.
- Dismantling the old compressor (cutting off the tubes).
- Installing a new unit and soldering connections.
- Evacuating the system to remove moisture and air.
- Refilling with the exact amount of freon.
The cost of such repairs often makes up a significant part of the price of a new refrigerator. Therefore, if your unit is more than 10-12 years old, sometimes it is more advisable to purchase new equipment than to invest in the reanimation of the old one. However, for modern models, replacing the compressor is the only way to extend the life of the device.
Do not delay contacting service. Prolonged attempts to start a faulty compressor can cause the wiring inside the refrigerator cabinet to burn out or the thermostat to fail. Taking good care of your equipment and timely diagnostics will save your money and nerves.
Why does the refrigerator click but does not turn on?
This is a classic symptom of a faulty start relay or jammed compressor. The relay tries to start the engine, but due to a breakdown it cannot keep the circuit closed, and the protection immediately opens the contacts.
Is it dangerous to continue using the refrigerator if it clicks?
Yes, it is dangerous. Constant attempts to start lead to overheating of the wiring and the compressor itself, which creates a risk of fire. In addition, the food in the chamber will begin to deteriorate due to the lack of cold.
Is it possible to replace the start relay yourself?
Yes, if you have basic skills in working with electricity and tools. The main thing is to buy a relay with exactly the same markings and follow safety precautions when turning off the power.
How much does it cost to replace a compressor?
The price consists of the cost of a new compressor, materials (freon, solder) and the work of a technician. On average, this can range from 30% to 60% of the cost of a new refrigerator of the same class.