A sudden failure of refrigeration equipment is always stressful, threatening food spoilage and financial losses. When the device ceases to maintain the set temperature, makes strange sounds or becomes covered with ice, it is important to quickly diagnose the cause. Understanding the design of the unit helps to distinguish a minor malfunction that can be fixed independently from a serious breakdown that requires the intervention of a specialist.
Modern models, be it classic Indesit or high-tech Liebherrconsist of many interconnected nodes. The most vulnerable elements are often the heat dissipation system, control electronics and seals. In this article we will analyze the main components that fail most often and the symptoms of their failure.
Do not panic at the first signs of unstable operation. Sometimes it is enough to defrost the camera or replace the light bulb. However, ignoring alarm signalssuch as the hum of the compressor or the formation of a “snow coat” can lead to expensive repairs or complete replacement of equipment.
Compressor: the heart of the refrigeration system
The compressor is the main engine cooling cycle, compressing the refrigerant and ensuring its circulation through the tubes. If this unit fails, the refrigerator stops cooling completely. Signs of a malfunction may be the absence of a characteristic hum when turned on or, conversely, continuous operation without stopping.
A frequent problem is the interturn short circuit electric motor windings. In this case, the motor may hum, but not start, or the automatic fuse in the electrical network may be knocked out. Also, mechanical wear of the piston group leads to loss of compression, due to which the pressure in the system drops and the freon does not condense properly.
⚠️ Attention: An attempt to independently replace the compressor without special equipment for evacuation and refilling with freon will lead to final breakdown of the system. The sealed circuit cannot be opened at home.
Another common cause of failure is the failure of the start-up relay. This small element is responsible for starting the engine and protecting it from overloads. If the relay “sticks” or burns out, the compressor will not receive an impulse to start, although electricity will be supplied to it.
Problems with the defrosting system and sensors
In models with the system No Frost a proper evaporator defrost cycle is critical. If this process is disrupted, an ice crust grows on the radiator, blocking the access of cold air to the chambers. The main culprits here are the evaporator heating element, defrost thermostat or defrost sensor.
The heating element (tubular electric heater) can burn out, stopping heating the evaporator to melt the ice. You can check its integrity with a multimeter in dial mode. If the circuit is broken, the heating element must be replaced. The defrost sensor behaves similarly, which “does not see” the need to start heating.
- 🧊 Ice build-up on the back wall even in modes without frost.
- 🌡️ The temperature in the chamber is higher than normal, although the compressor is working.
- 🔊 Clicking when trying turning on defrosting.
- 💧 Water under the refrigerator due to overflow of the drain pan.
It is also worth paying attention to the drainage system. If the condensate drain hole is clogged with debris or ice, water begins to accumulate at the bottom of the refrigerator and flow out. Regular cleaning of the drainage with a soft wire or brush helps to avoid this problem.
Why do sensors lie?
Temperature and defrost sensors change their resistance over time. Even if they are intact, their readings can shift, causing the controller to make mistakes in calculating the time when the compressor or heating element is turned on.
Malfunctions of the thermostat and control electronics
A thermostat (thermostat) is a mechanical or electronic device that controls the temperature inside the chambers and sends a signal to turn the compressor on or off. If the refrigerator “does not know” when to stop, the food freezes, and if it cannot start, it defrosts.
In mechanical models, the capillary tube of the thermostat may lose its seal over time, and the filler gas will evaporate. As a result, the contacts simply stop closing. In electronic control boards, capacitors or tracks often fail due to power surges in the network.
Symptoms of thermostat failure are quite specific: the compressor either does not turn on at all or works without interruption, causing severe freezing. In modern models with a display, the sensor error is often displayed in the form of a code that can be deciphered in the instructions.
Refrigerant leakage and system blockages
The refrigerant (freon) circulates in a closed circuit, and in a working refrigerator its quantity does not change for years. However, mechanical damage, corrosion of the evaporator tubes (especially in models with a foamed circuit) or poor-quality factory welding can lead to leakage.
Leakage symptoms include a lack of cold when the compressor is running, which may become hotter than usual. Also, there may be no condensation on the tubes near the motor, and oily stains are sometimes (but not always) visible at the leak site, since freon circulates along with the compressor oil.
Clogged capillary tube is another problem that often occurs due to moisture or compressor wear products getting into the system. In this case, the compressor is overloaded, trying to push freon, but no cooling occurs. You can determine the blockage by the temperature of the condenser: it will be hot only at the beginning, and then cool down.
Mechanical damage and wear of seals
The rubber door seal is the first barrier that keeps the cold inside. Over time, the rubber hardens, cracks or deforms, no longer fitting tightly to the body. Warm, moist air enters through the resulting cracks, causing the compressor to work harder.
You can check the tightness in a simple way: clamp a sheet of paper between the door and the housing in different places. If the sheet is pulled out without resistance, then the fit is broken. You can restore elasticity by heating it with a hairdryer, but if there is severe wear, only replacement will help.
Mechanical damage also includes dents on the body, which can pinch the internal tubes, and broken shelves. Particular attention should be paid to the door hinges: if they sag, the door warps and the seal stops performing its function even in perfect condition.
☑️ Diagnosis of the seal
Table of symptoms and probable causes
To quickly navigate the problem, use the pivot table. It will help narrow down the troubleshooting before calling a technician.
| Symptom | Probable cause | Difficulty of repair |
|---|---|---|
| Does not turn on, no light | No power, burnt out socket, faulty cord | Low |
| Humming, but not freezing | Freon leak, blockage, compressor faulty | High |
| Ice builds up in No Frost | The heating element, defrost sensor or timer has burned out | Medium |
| Water is flowing inside | Drainage clogged, incorrect installation | Low |
| Extremely freezing | Thermostat or temperature sensor is faulty | Medium |
It is important to understand that one symptom can indicate different breakdowns. For example, a lack of cold occurs both when there is a leak and when the compressor breaks down. An accurate diagnosis can only be made by a specialist using a pressure gauge manifold and a tester.
The critical point is the reaction time: If you notice that the refrigerator has stopped freezing, the food must be immediately refrigerated, and the equipment must be defrosted and dried before diagnosis, so as not to burn the compressor when turned on again.
Frequently asked questions (FAQ)
Why does the refrigerator work continuously and does not turn off?
Most often this indicates a refrigerant leak, when the power of the remaining gas is not enough to set the temperature, or a malfunction of the thermostat, which “does not see” the cold. Also, the reason may be a dirty condenser at the back of the equipment, which does not give off heat.
Is it possible to replace the compressor yourself?
No, this cannot be done without special tools. To replace it, you need to open the sealed circuit, remove the old motor, weld in a new one, create a vacuum in the system and fill in the exact amount of freon. This is a job for the service center.
What to do if water appears inside the refrigerator?
First of all, check the drainage hole on the back wall. It often becomes clogged with crumbs or ice. Clean it with a special wire or a cotton swab. If water flows in a stream, the internal plastic tray may be cracked.
How often do you need to defrost a No Frost refrigerator?
The No Frost system does not require manual defrosting to remove ice, as this happens automatically. However, at least once a year, it is recommended to completely turn off the equipment, wash and dry the chambers for hygiene and check the operation of the moisture removal system.
Is it dangerous to continue to use the refrigerator if it hums loudly?
A loud hum may indicate vibration of the housing, but also that the compressor is overloaded or worn out. Long-term operation in this mode can lead to its final failure, so it is better to carry out diagnostics.