The situation when in the refrigerator Atlant the lower chamber continues to work properly, but the upper one stops cooling food, is one of the most common complaints from owners of this equipment. Users often encounter the fact that food begins to melt in the freezer compartment, or the temperature indicator in the main chamber (if it is on top) stops lighting. This does not always mean that the unit has completely failed, but the problem cannot be ignored, since the products can deteriorate in a matter of hours.
The main reason lies in the disruption of refrigerant circulation or failures in the temperature control system. Modern models, such as Atlant XM 4008 or 4502, are equipped with a No Frost system, where cold air is pumped by a fan. If this mechanism fails, the cold simply does not reach the upper shelves. In simpler models with a crying evaporator, the problem may lie in a clogged capillary tube or a freon leak.
Before calling a technician, it is important to carry out an initial diagnosis in order to understand the scale of the disaster. DIY Repair is possible only if you accurately have identified the cause and have the appropriate tools. In most cases, the problem is solved by replacing the thermostat or defrosting the system, but sometimes more complex intervention in the hydraulic circuit is required.
Checking the thermostat and temperature sensor
The first element that needs to be checked is the thermostat (thermostat) or electronic temperature sensor, depending depending on your refrigerator model. It is this unit that “tells” the compressor when it needs to turn on in order to maintain the desired cold. If the thermostat is stuck in the off position or shows incorrect data, the compressor simply will not start and the upper chamber will begin to heat up.
In mechanical models, the thermostat is usually located inside the chamber or on the control panel. To check its functionality, you can try turning the control knob all the way to the right and left. If you do not hear a characteristic click, the mechanism is most likely faulty. In electronic models Atlant with a display, a sensor malfunction is often indicated by an error code, for example, a flashing temperature indicator.
Replacing the thermostat is a relatively simple procedure, but requires care. It is important to choose an analogue with identical parameters, since installing an unsuitable part will lead to an incorrect compressor operating cycle. Incorrect temperature conditions can cause rapid spoilage of products or the formation of excessive ice.
Where is the thermostat located in different models?
B In classic two-chamber Atlant refrigerators, the thermostat is often hidden under a plastic cover inside the refrigerator compartment, next to the light bulb. In models with electronic control, sensors are mounted in the chamber wall or in the air duct.
Problems with the fan and the No Frost system
If your Atlant is equipped with a No Frost system, then the lack of cold in the upper part (usually this is the freezer compartment, but it happens the other way around, depending on the design) often indicates that the fan has stopped. This unit is responsible for the forced circulation of cooled air from the evaporator to the shelves. If the fan is stopped, cold air remains in the evaporator area, and heat enters the chamber.
The reasons for stopping the fan can be different: from banal icing of the blades to failure of the electric motor. You can often hear a humming or crackling sound coming from the rear wall of the chamber, which indicates that the engine is trying to start. In some cases, the fan blades freeze to the wall due to ice formed, and the motor simply cannot turn them.
- ❄️ Icing of the blades due to a malfunction of the defrost heating element.
- ⚙️ Wear of the fan motor bearings, causing jamming.
- 🔌 Broken wiring or oxidation of contacts going to the motor.
To check, you need to dismantle the back panel in the freezer. Visually inspect the fan for ice and mechanical damage. If the fan spins manually easily, but does not work from the mains, most likely the winding is burned out or there is a problem in the control board. Air circulation is a key factor for the operation of the No Frost system.
Faults in the compressor and start relay
Compressor - This is the “heart” of the refrigerator, and if it does not work or does not work correctly, there will be no cold anywhere, but sometimes the symptoms appear unevenly. In two-compressor models Atlant different motors are responsible for the upper and lower chambers. If the top does not freeze, then the problem is with the upper compressor or its piping.
A frequent cause of failure is the failure of the start-up relay. This small unit is responsible for starting the compressor motor. If the relay is burned out, the compressor may hum, try to start, but after a few seconds turn off with a characteristic click. In this case, the motor does not gain the required speed, and the refrigerant does not circulate through the system.
⚠️ Attention: If the compressor is hot to the touch, but the refrigerator does not freeze, do not under any circumstances try to start it again without eliminating the cause. This can lead to a wedge of the piston group and an expensive replacement of the entire unit. Allow the equipment to cool for at least 2-3 hours before re-diagnosis.
It is also worth paying attention to the operation of the compressor itself. If it runs continuously without turning off, but there is no cold, this may indicate a loss of performance (wear of the valves) or a freon leak. In two-compressor models, compare the operation of both motors: if the lower one works cyclically (turns on and off), and the upper one hums constantly or is silent, the diagnosis is obvious.
Freon leak and clogged capillary system
One of the most unpleasant reasons why the upper part does not freeze is a refrigerant (freon) leak or a clogged capillary tube. Freon circulates in a closed circuit, taking away heat. If its quantity decreases, the pressure in the system drops, and the refrigerant simply does not reach the evaporator in the upper chamber, evaporating earlier.
Leaks often occur in places where tubes are soldered or in the foamed part of the housing (inside the walls), where the metal corrodes over time. Signs of a leak are: a slightly hot condenser (grid at the back), no characteristic gurgling noise during operation, and continuous operation of the compressor. A clogged capillary tube gives similar symptoms, but is often accompanied by freezing of the filter-drier.
It is almost impossible to eliminate a leak or blockage on your own without special equipment (vacuum pump, pressure gauge station, burner). It requires searching for the leak, soldering, evacuation of the system and precise refilling with freon. Attempting to refill yourself “by eye” without evacuation will lead to rapid breakdown of the compressor due to moisture in the system.
Is it possible to refill the refrigerator yourself?
Theoretically it is possible if you have the equipment. But in practice, 90% of such attempts end in calling the technician again with a different payment. Freon R600a, used in Atlanta, is explosive, which requires special care.
Failure of the defrost heating element and timer
In refrigerators with the No Frost system, the proper operation of the defrost circuit is critical. If the heating element (heating element), defrost timer or defrost sensor fails, a “coat” of ice begins to grow on the evaporator. Over time, this ice completely blocks the channels through which cold air should enter the chamber.
Visually it looks like this: the fan is humming, the compressor is running, but there is no cold, because the air flow is blocked by ice. Often in such cases, you will notice that the back wall of the chamber is swollen or covered with frost. After some time, the ice may melt naturally (if you defrost the refrigerator for 24 hours), and the cold will appear again, but only until the next freezing cycle.
- 🔥 Burnout of the defrost heating element coil.
- ⏱️ Malfunction of the timer or electronic defrost control module.
- 🌡️ Failure of the defrost temperature sensor (defroster).
For diagnostics, you need to remove the back panel in the freezer and inspect the evaporator. If it is covered in ice, and the heating element located under it is cold and does not ring with the tester, the reason has been found. It is also worth checking the defrost sensor, which should open the heating element circuit when a certain temperature is reached.
⚠️ Attention: Do not use sharp objects (knife, screwdriver) to chip ice from the evaporator! You may damage the aluminum tubes or heating element, resulting in an immediate freon leak or short circuit. Defrost only naturally.
☑️ Diagnostics of the defrost system
Fault diagnosis table
To To systematize the knowledge gained and quickly determine the cause of the breakdown, use the table of symptoms. It will help narrow down the troubleshooting before calling a specialist.
| Symptom | Probable cause | Difficulty of repair |
|---|---|---|
| The compressor does not turn on, there is no light | No power, Thermostat burned out | Low |
| Buzzes, clicks, but does not start | Faulty starting relay or compressor wedge | Medium |
| Works constantly, cold low | Freon leak or blockage | High (needs a technician) |
| The fan does not spin, there is ice | Faulty defrost heating element or sensor | Medium |
| Indicator flashes, display error | Electronics or sensors failure | Medium/High |
This table covers the most common scenarios. However, it is worth considering that in modern models Atlant with electronic control, one primary fault can cause a chain reaction of errors. For example, a freon leak can lead to overheating of the compressor and subsequent failure of the control board.
When you need to call a professional technician
Despite the desire to save money and repair the equipment yourself, there are situations where the intervention of an unqualified user will only aggravate the situation. If diagnostics indicate problems with the sealed circuit (leaks, blockages), specialized equipment is required. The technician has tools for vacuuming the system and accurately dosed freon filling.
You should also contact professionals if the problem lies in the electronic control module. Refrigerator control boards Atlant can have complex circuit solutions, and simply resoldering the capacitor does not always solve the problem. In addition, after replacing a compressor or capillary tube, high-quality soldering is required in a nitrogen protective environment to avoid oxidation of the system from the inside.
- 🛠️ Welding or soldering of copper pipes of the circuit is required.
- 💻 Re-flashing or complex repair of an electronic board.
- 🔍 It is not possible to visually determine the cause after a basic check.
Remember that a timely call to a technician can save the compressor from complete failure. If the refrigerator stops freezing, do not delay repairs. Products in a defrosted state are not stored for long, and prolonged downtime of equipment with a faulty compressor can lead to burnout of the windings.
Frequently asked questions (FAQ)
How long should the system dry after defrosting?
For the ice to completely melt and moisture to evaporate in the No Frost system, the refrigerator must be turned off with the doors open for at least 24 hours. If you simply turn it off for a couple of hours, the water may remain in the channels and freeze again, blocking the fan.
Is it possible to operate the refrigerator if the upper chamber does not freeze?
For a short time - yes, if the lower chamber is working. But you can’t use the equipment like this for a long time. The compressor will work hard, trying to gain temperature, which will lead to overheating and failure. In addition, bacteria will begin to multiply in a warm chamber.
Why did the refrigerator work after defrosting, but after a week it stopped again?
This is a classic sign of a malfunction of the defrost system (heating element, timer or sensor). The ice freezes again and blocks the channels. Defrosting is a temporary solution; it is necessary to replace the faulty element of the defrost circuit.
Where can I find the electrical diagram for the Atlant refrigerator?
The electrical diagram is usually pasted on the plastic compressor casing at the back of the refrigerator or is in the operating instructions. Also, diagrams can be found on the manufacturer’s official website in the support section for a specific serial number.