A sudden failure of refrigeration equipment always becomes an unpleasant surprise, because the safety of food and your comfort directly depend on it. When the unit stops freezing, makes strange sounds, or becomes covered in ice, it is important to quickly determine the nature of the malfunction in order to understand whether the problem can be solved on your own or whether you need to call a technician. Most modern models, be it Bosch, LG or Indesit, have a similar design, so typical faults are often repeated.
Timely diagnostics can not only save your budget on expensive repairs, but also prevent the spoilage of a large amount of food. In this article, we will analyze in detail the main types of breakdowns, their symptoms and causes, so that you can confidently navigate the situation. Understanding the principles of operation of the components will help you distinguish a minor malfunction from a serious breakdown of the compressor. Attention: If you smell burning or see sparking, immediately disconnect the device from the power supply. Further operation may lead to a fire or failure of the wiring in the apartment. compressor.
⚠️ Attention: If you smell burning or see sparking, immediately disconnect the device from the power supply. Further use may lead to a fire or failure of the wiring in the apartment.
Problems with the cooling system and compressor
The heart of any refrigeration unit is the compressor, which circulates the refrigerant throughout the system. If you notice that the engine is humming but does not start, or, conversely, is running non-stop without turning off, this is an alarming signal. Often the cause is a failure of the starting relay or the electric motor itself. In such cases, the unit may stop gaining temperature altogether or, on the contrary, freeze all the food in the refrigerator compartment.
Another common problem is a freon leak. The refrigerant circulates through the sealed circuit, but over time the metal can become corroded or mechanically damaged. Symptoms of a leak include poor cooling, hot side walls (instead of barely warm) and continuous operation of the compressor. Refilling with freon requires special equipment and qualifications, so you can’t do it yourself.
Often owners are faced with a clogged capillary tubes. This is a thin element where the refrigerant is throttled, and it becomes clogged with oil breakdown products or moisture. If clogged, the compressor operates jerkily, and the freezer may only be partially covered with frost. To clean the system, vacuuming and purging with nitrogen are required.
⚠️ Attempts to replace the compressor yourself without replacing the filter-drier and proper vacuumization of the system will lead to a quick re-breakdown of the expensive unit.
Faults in the thermostat and sensors
A thermostat (thermostat) or an electronic temperature sensor is responsible for maintaining the set temperature. If the refrigerator freezes too much, turning vegetables into ice blocks, or, conversely, stops turning off, the problem most likely lies here. In mechanical models, the thermostat is a capillary tube with a bellows, which over time loses its tightness or sensitivity.
In modern models with a system No Frost and electronic control, thermistors are used instead of mechanics. Their resistance changes depending on temperature, and the control module reads these readings. If the sensor is lying, the system may not start defrosting or, conversely, may not turn on the compressor. Replacing these elements usually does not take much time and is relatively inexpensive.
Diagnostics of the thermostat is often carried out by the method of exclusion. If the compressor starts when the contacts are closed, and stops when the contacts are opened, it means that the motor itself is working, and you need to look in the control circuit. In electronic boards, a burnt-out sensor is often displayed as an error code on the display, which greatly simplifies troubleshooting.
Failures of the defrost system (No Frost)
Refrigerators with a system No Frost eliminate the need for manual defrosting, but add additional components to the design that can break. The key elements here are the evaporator heating element, the defrost timer (or electronic module) and the thermal fuse. If you see that the back wall of the freezer is covered with a “coat” of ice, and the fan is humming but not blowing, it means that the defrosting system is not working.
Most often, the heating element coil burns out, which is supposed to melt the ice on the evaporator during the defrosting cycle. Ice accumulates, blocks the air dampers, and the cold stops flowing into the refrigerator compartment, although it may be normal in the freezer. The heating element is checked with a multimeter for an open circuit.
The defrost sensor, which tells the control module that the ice has melted, also often fails. If it does not give a signal, the heating element may heat for too long or not turn on at all. In some models, the problem becomes the drainage hole, which becomes clogged with dirt, and the melt water does not leave, but freezes at the bottom of the chamber.
☑️ Diagnostics of the No Frost system
Mechanical damage and problems with seals
The breakdown is not always associated with electrical or refrigerant. Mechanical damage to the body, dents on the doors or wear of the sealing rubber can lead to serious malfunctions. If the door does not fit tightly, warm air constantly enters the chamber, which causes the compressor to wear out, and condensation and ice form on the walls.
The sealing gum becomes dull over time, cracks, or comes away from the body. You can check the tightness using a simple sheet of paper: clamp it with the door and try to pull it out. If the paper is pulled out without resistance, it means the seal is broken. In some cases, the rubber band can be restored using a hairdryer or boiling water, but more often replacement is required.
Mechanical damage to the evaporator tubes due to careless defrosting with a knife is a classic mistake leading to an instant leak of freon. If you pierce the wall and hear a hissing sound, do not turn on the refrigerator under any circumstances. Air and moisture trapped inside will lead to corrosion of the compressor from the inside if the system is started.
How to defrost a refrigerator correctly?
Never use sharp objects to chip ice. The best way is to turn off the appliance, place bowls of hot water inside and close the door for 15-20 minutes. The ice will quickly thaw on its own.
Noise, vibration and extraneous sounds
The refrigerator is not a silent device, but the nature of the sounds can say a lot about its condition. Loud humming, knocking, gurgling or whistling often indicate specific problems. For example, severe vibration may be caused by improper installation: if the legs are not adjusted and the housing is skewed, the compressor will resonate with the floor.
A knocking or clanging sound when starting the engine often indicates problems with the start relay or wear on the compressor piston group. If you hear a whistling sound, there may be a problem with the drive belt (in older dual-compressor models) or the fan blades rubbing against ice. Gurgling and overflowing are usually normal and indicate the movement of freon, but if the sound becomes too loud, there may be air in the system.
| Type of sound | Probable cause | Degree of danger |
|---|---|---|
| Uniform humming | Normal compressor operation | Normal |
| Loud clicking and silence | Faulty start relay | Medium |
| Whistling or squeak | Fan or belt friction | Low |
| Gurgling of water | Movement of freon/water in the drainage | Normal |