A sudden stop in the operation of refrigeration equipment always takes you by surprise, turning into a serious household problem. Products begin to deteriorate, there is a risk of large volumes of inventory defrosting, and the wait for a technician may take several days. It is at such moments that the ability to conduct an initial diagnosis becomes a critical skill for any owner of household appliances.
Before you panic or look for a service center number, you need to assess the situation. Often the reason lies in trivial things: the plug has come out of the socket, the automatic switch in the control panel has tripped, or the temperature setting has accidentally gone wrong. However, if external factors are excluded, you will have to look for the problem inside the unit.
Understanding the basic principles of operation compressor and the refrigerant circulation system will help you more accurately describe the symptoms to a specialist or even fix the problem yourself. In this article we will analyze an algorithm for finding defects that will save time and money.
Initial visual inspection and power check
Any diagnostics begins with checking basic things. Make sure the power cord is intact and the plug is firmly seated in the outlet. Sometimes the problem is solved by simply rebooting the device: unplug the refrigerator for 10-15 minutes, and then turn it on again. This will allow electronic module to reset errors.
Carefully inspect the rear wall of the unit. The absence of dust and dirt is the key to normal heat transfer. If the condenser (black grille at the back) is covered with a dense layer of dust, the compressor may overheat and go into protection. Also check to see if the refrigerator is too close to the wall, which would impede air circulation.
⚠️ Attention: Before any inspection of the internal electrical components, be sure to unplug the unit to avoid electric shock.
Pay attention to the indicators on the control panel, if any. Flashing lights or error codes on the display are a direct signal from the system self-diagnosis. The decoding of the codes for your model Indesit or LG can be found in the instructions or on the manufacturer's official website.
☑️ Initial inspection
Analysis of the operation of the compressor and start relay
The heart of the refrigerator is compressor. If it does not start but hums, or makes clicking noises but is silent, the problem most likely lies in the start protection relay or the motor itself. In good condition, the compressor operates cyclically: it turns on, cools the chamber, turns off.
If you hear a characteristic click, followed by a hum that lasts several seconds, and then another click and silence, this is a sign of a faulty start relay or jammed piston group. In the first case, the repair is cheap and simple, in the second, the unit will need to be replaced.
To check the relay, it must be removed from the compressor (after photographing the connection) and shaken. If a ringing sound is heard inside, it means the contacts are damaged. Also visually inspect the contacts for carbon deposits or oxidation.
How to check the compressor directly
For experienced users: you can apply 220V voltage directly to the compressor windings, bypassing the relay. If the engine starts, the relay is faulty. If it hums and does not turn, the compressor is jammed. Be careful, it is dangerous!
It is important to distinguish between a noisy unit and abnormal sounds. A knocking, clanging or piercing whistle indicates mechanical damage to the internal components pump.
Checking the thermostat and temperature sensors
If the compressor hums constantly and does not turn off, or does not respond at all to the increase in temperature in the chamber, it is worth checking thermostat (thermostat). In older models, this is a mechanical device with a capillary tube, in new ones - electronic sensors.
For a mechanical thermostat, there is a simple test: with the refrigerator running, turn the control knob to the "0" or "Off" position. There should be a click and the compressor will stop. If this does not happen, the contacts are stuck or the device is faulty.
In models with the system No Frost electronic sensors monitor the temperature. Their resistance changes depending on the heat. The test is carried out with a multimeter: when the ambient temperature changes, the resistance readings should change. If the values stay the same, the sensor is dead.
| Symptom | Probable cause | Check method |
|---|---|---|
| The refrigerator does not turn on | No power or the thermostat is burnt out | Checking the thermostat with a multimeter |
| Works without stopping | Freon leak or faulty thermostat | Checking the pressure in the system |
| Frequent on/off | Malfunction of the starting relay | Visual inspection of the relay |
| Poor cooling | Clogged filter or leakage | Inspection of the filter drier |
Diagnostics of the defrosting system (for No Frost)
In refrigerators with a system No Frost a frequent reason for stopping cooling is a failure in the evaporator defrost system. If the defrost heating element, timer or defrost sensor fails, a “coat” of ice builds up on the evaporator, which blocks the circulation of cold air.
The symptoms are simple: food is frozen in the freezer compartment, but it is warm in the refrigerator compartment, or the fan is humming, but no air is blowing. This can be confirmed visually by getting to the evaporator (removing the back panel in the freezer). A thick layer of ice will confirm the diagnosis.
It is necessary to check the integrity of the defrost heating element. It should be called by the tester. The defrost sensor is also checked, which gives the command to turn on the heating. If the chain is broken, the ice will not melt and the system will go into emergency mode.
⚠️ Attention: Do not try to pick out the ice with a knife or sharp objects! You can puncture the evaporator tubes, which will lead to an immediate leak of freon and expensive repairs.
It takes time to completely defrost the unit. Leave the refrigerator turned off with the doors open for at least 24 hours. Only after the ice has completely melted can you try to turn it on again to test the hypothesis.
Search for refrigerant leaks and blockages
If the compressor is running without stopping, the freezer barely freezes, and there is no frost on the tubes inside the chambers (or there is only frost at the entrance), it is likely freon leakage. The refrigerant circulates in a closed circuit, and its quantity should not change during its service life.
Leaks often occur at soldering points, in the foamed part of the body (due to corrosion) or in the heating circuit of the door perimeter. It is difficult to visually find the location of the leak; often oily spots remain on the tubes - these are traces of compressor oil that came out along with the gas.
Clogged capillary tube is another reason for the lack of cold. This can happen due to moisture in the system or compressor wear. When clogged, the filter drier (the copper cylinder of the compressor) may become covered with frost or, conversely, be very hot.
It is impossible to refill the refrigerator yourself or find a micro-crack without special equipment (leak detector, pressure gauge station). This requires the intervention of a specialist with a license to work with refrigerants.
Problems with the seal and the tightness of the chambers
Often the reason for ineffective operation lies in the loose fit of the door. Rubber seal Over time it becomes tanned, cracks or deforms. Warm, moist air enters the chamber through the cracks, forcing the compressor to wear out.
You can check the tightness using a regular sheet of paper. Clamp the sheet with the door around the perimeter. If it pulls out easily and without resistance, the seal does not fit in this place. Pay special attention to the corners and folds.
Sometimes the seal is simply contaminated with grease or sticky dirt. Washing thoroughly with warm water and soap can restore its elasticity and stickiness. If the rubber is torn or severely deformed, replacement will be required.
When you need to call a specialist
Despite the desire to save money, there are situations when independent repairs are dangerous or impractical. Opening the sealed circuit of the cooling system without skills and tools is guaranteed to ruin the equipment.
If you find that the problem is related to the electronic control module (burnt tracks, swollen capacitors), it is better to entrust the soldering to a professional. Improper repair of the board can lead to a short circuit and fire.
A technician is also needed if the compressor needs to be replaced. This process involves soldering the pipes, evacuating the system, and accurately charging the refrigerant by weight. Errors here are fatal for the refrigerator.
⚠️ Attention: If you smell burning or see sparking in the compressor area, immediately unplug the refrigerator and do not turn it on until the technician arrives.
Frequently asked questions (FAQ)
Why is the refrigerator so hot? hums after installation?
If the unit has just been delivered, the transport stability may have been compromised. Check if the refrigerator is level and tighten the legs. Also, the new compressor may be noisier during the break-in period (up to 3-5 days).
Is it possible to use a refrigerator if it makes noise, but freezes?
For a short period of time, it is possible. However, increased noise often predicts compressor or fan bearing failure. It is better not to delay diagnostics so as not to be left without food at the wrong time.
How often should you defrost a No Frost refrigerator?
The system No Frost assumes automatic defrosting. It is necessary to forcibly defrost such a refrigerator only in case of breakdown of the defrost system or for general cleaning, approximately once every 1-2 years.
Why does ice form on the back wall inside the refrigerator?
In drip systems this is normal when the compressor is running (the ice melts during the rest cycle). If the ice does not melt or there is too much of it, check the drainage hole on the back wall - it could be clogged with debris.