The situation when you open the refrigerator, and there is room temperature, can ruin anyone’s mood. It is especially alarming if the food in the lower chamber has already begun to deteriorate, and the upper shelf, on the contrary, is covered with an ice crust. This is a classic cooling system failure scenario that requires immediate attention. Ignoring the problem can lead to complete breakdown of an expensive unit and loss of food stock.
In modern models, be it Indesit, Stinol, LG or Atlant, cold circulation is often tied to a single system, where the failure of one unit affects all compartments. If the bottom stops freezing, this does not always mean that it broke right there. Often the root of evil lies in the upper part of the chamber or even in the engine compartment. Primary diagnosis will help you understand whether it is worth calling a technician or you can try to fix the situation yourself.
In this article we will analyze in detail the mechanics of the process, possible malfunctions and an algorithm of actions. It is important to understand that compressor can work without stopping, but there will be no cold if the seal is broken or the capillary is clogged. Let's figure out why the equipment behaves strangely and how to return it to functionality.
The principle of operation of the No Frost and static cooling system
To understand the cause of the breakdown, you need to know how the cold gets into the lower chamber. In refrigerators with static cooling (drip system), the evaporator is located in the rear wall of the main chamber. Cold air naturally sinks down, cooling food. If it is warm below, it means that the cold flow does not reach the target or its generation is disrupted.
In systems No Frost ("without frost") everything is more complicated. The evaporator is hidden behind a plastic panel, usually at the top or behind the back wall. The air is driven through it by a fan and supplied through special channels to the chambers. Air circulation is the key point. If the channel is clogged with ice or blocked with food, the bottom of the refrigerator stops freezing, even if the top part is operating normally.
The difference in the operation of the systems also determines the troubleshooting strategy. In “crying” models, leaks or problems with the thermostat are most often to blame. In systems No Frost the range of problems is wider: from a burnt-out fan motor to a defrost sensor failure.
⚠️ Attention: If you hear that the compressor is humming, but does not start (a clicking and humming noise is heard), immediately disconnect the device from the network. Repeated starting attempts can burn out the motor windings or the starting relay.
Natural reasons: when it’s too early to panic
Before you grab the tools, you should exclude trivial things. Sometimes the reason why the bottom of the refrigerator does not freezelies not in a breakdown, but in improper operation. For example, you just defrosted the unit and turned it on, loading the shelves with food. In this case, the equipment needs time (from 4 to 8 hours) to reach the temperature.
Another common reason is violation of loading rules. If you pressed the shelves tightly against the back wall, you could be blocking the cold air ducts. In models with No Frost this is critical: the air must circulate freely. Also check if the refrigerator door is pressed against food, which is why it does not close tightly.
The temperature in the room also plays a role. If the refrigerator is located next to a radiator, stove, or in direct sun, the cooling system may not be able to cope with the heat flow. The compressor will work for wear, but will not provide the required cold. Also check the settings: perhaps one of the household members accidentally switched the regulator to the “minimum” mode or turned on the “vacation” mode.
- 🧊 Overload: too many warm foods placed at the same time.
- 🚪 Loose fit: a door misalignment or contamination of the seal interfere with the seal.
- ❄️ Operating mode: fast freezing mode is turned on, which must be turned off manually after a while.
Faults in defrosting systems (for No Frost)
If you have a model with No Frost, and the bottom has stopped freezing, and snow or ice is visible on the back wall of the main chamber, the problem is almost certainly in the defrost system. The evaporator becomes overgrown with a “fur coat” that blocks the air supply channels. The fan is humming, but the air simply cannot break through the ice plug to the bottom shelf.
A chain of elements is responsible for the defrosting process: Evaporator heating element, defrost sensor (defroster) and defrost relay (timer or electronic module). If the heating element burns out, the ice does not melt. If the sensor “lies” and shows that the evaporator is warm, the control module will not turn on the heating. As a result, an ice monolith grows over several days or weeks.
You can diagnose this visually by getting to the evaporator, or by checking the resistance of the heating element with a multimeter. Often it is the heating element or the fuse built into the circuit that fails. Replacing these parts usually brings the refrigerator back to life.
Problems with the compressor and start relay
Compressor are the heart of the refrigerator. If it does not work or does not work correctly, there will be no cold anywhere, but sometimes there are nuances. For example, a compressor may hum but not start due to a jam or electrical problem. In such cases, the bottom does not freeze because freon does not circulate through the system.
Often the culprit is starting relay. This is a small part that fits onto the compressor contact. Over time, the contacts in the relay burn out, or the bimetallic strip loses its properties. The compressor tries to start, a clicking sound is heard, a humming sound, but after a few seconds it turns off. The cycle repeats.
Replacing the relay is one of the simplest and cheapest repair procedures. However, if after replacing the relay the compressor still does not start or gets hot, the problem may be in the motor itself (turn-to-turn short circuit) or in the wiring. In this case, more serious repairs or replacement of the unit are required.
☑️ Compressor diagnostics
Refrigerant leak and capillary system blockage
One of the most unpleasant reasons why not the bottom of the refrigerator freezes - this freon leak. The refrigerant can escape through microcracks in the evaporator (often due to corrosion or mechanical damage due to careless defrosting) or in places where the tubes are soldered. When there is a leak, the pressure in the system drops and the cooling capacity decreases sharply.
The second option is clogging of the capillary tube. Oil and freon circulate in the system. Over time, an ice or oil plug may form in the tube, or moisture may enter there. Freon cannot pass into the evaporator in the required volume. A characteristic sign of a blockage is a hot condenser (grid at the back) and only a cold section of the tube up to the point of blockage.
In both cases, a call to the technician is required. It is impossible to independently find a leak or break through a blockage without special equipment (vacuum pump, pressure gauge station, burner). The technician will determine the location of the damage, seal it, replace the filter drier and fill the system with new freon.
| Symptom | Probable cause | Nature of compressor operation |
|---|---|---|
| Ice on the back wall | Faulty defrost system | Works without stopping |
| The compressor is hot | Freon leak or blockage | Works for a long time or constantly |
| Clicks and buzzing | Malfunction of the start relay | Short attempts to start |
| The refrigerator is silent | Electronics failure or open circuit | Not included |