The situation when Atlant refrigerator stops turning off is familiar to many owners of this popular equipment. The compressor hums continuously, creating the feeling that the unit is about to fail, and electricity bills are rising exponentially. This is not just noise, it is a signal that the cooling system is operating in emergency mode, trying to reach temperatures that it physically cannot reach due to a specific malfunction.
Constant operation of the motor leads to overheating of the windings and rapid wear of the piston group. If you don't intervene in time, a simple repair can turn into an expensive compressor replacement. In this article we will look in detail at why double-chamber refrigerator or a single-chamber model works without interruption and how to localize the problem.
The first thing to do is to eliminate external factors. Perhaps you simply forgot to close the door tightly after loading the products, or warm air got into the chamber due to a long opening. However, if the door is closed, the seal is intact, and the hum has not stopped for several hours, then it’s time for a deeper diagnosis.
The main reasons for the continuous operation of the compressor
There are several key components, the failure of which leads to the fact that the equipment does not see the command to stop. Most often the culprit is the thermostat. This element is responsible for controlling the temperature inside the chambers. If the sensor is “stuck” in the “on” position or its contacts are oxidized, the compressor will work endlessly without receiving a signal that the desired degree has been reached.
⚠️ Attention: If you hear a characteristic click, but the compressor does not start or, conversely, does not stop, the problem may lie in the start-protection relay. In some models Atlant the relay may stick, transmitting direct current to the motor windings.
The second common option is a refrigerant leak. When the system becomes low on freon, the pressure drops and the compressor is forced to work harder, trying to compensate for the lack of cooling capacity. It hums but doesn't cool. The third option is a clogged capillary tube, which creates a similar effect, but with additional symptoms, such as swelling of the back wall.
It is also worth considering software failures if you have a modern model with electronic control. The electronic module may freeze or issue commands due to a power surge. In this case, a complete reboot of the system helps by disconnecting from the network for 15-20 minutes.
Diagnostics of the thermostat and temperature sensors
If your Atlant refrigerator does not turn off, in 60% of cases the thermostat (in mechanical models) or the air sensor (in models with No Frost and electronics) is to blame. A mechanical thermostat is a sealed flask with gas or liquid that responds to changes in temperature. Over time, the bellows loses its tightness or becomes deformed.
To check the mechanical thermostat in models like Atlant 4008 or Atlant 4502 often it is not necessary to disassemble the entire unit. It is enough to remove the plastic cover inside the refrigerator compartment where the regulator handle is attached. By carefully disconnecting the terminals, you can ring the contacts with a tester at different positions of the handle. If the circuit does not open even with strong cooling, the part needs to be replaced.
- 🔍 Symptom 1: The compressor works constantly, but the temperature in the chamber drops below normal (food freezes).
- ❄️ Symptom 2: The unit hums, but there is no cold at all, while the thermostat itself may be working, but does not “feel” the temperature due to the displacement of the tube.
- ⚡ Symptom 3: Periodic clicks without stopping the motor indicate burning of the contacts inside the relay thermostat.
In models with the system No Frost air sensors are responsible for the temperature. If such a sensor “lies” and shows that the chamber is warm, the control module will keep the compressor on. You can check it with a multimeter, measuring the resistance when the temperature changes (for example, holding the sensor in your hand).
How to replace the thermostat yourself?
To replace a mechanical thermostat you must: 1. Disconnect the refrigerator from the network. 2. Remove the regulator handle and decorative trim. 3. Unscrew the screws securing the thermostat housing. 4. Carefully pull the capillary tube out of the evaporator (without damaging it). 5. Install a new thermostat with the same markings. 6. Fix the tube in the same position as the old one.
Problems with refrigerant: leaks and blockages
When Atlant refrigerator it does not turn off, but does not cool, there is a high probability of a leak in the circuit. Freon is a working fluid that circulates through the system, taking away heat. If a microcrack forms (often in the foamed part of the body or at the junction of the tubes), the gas gradually evaporates.
The compressor tries to compensate for the lack of refrigerant, working for wear. The danger of the situation is that oil may leave the system along with freon, which will lead to jamming of the motor. It is difficult to notice a leak visually, but an indirect sign is a hot condenser (grid at the back) only at the beginning or at the end, and a cold one in the middle.
| Symptom | Freon leak | Clogged capillary | Malfunction compressor |
|---|---|---|---|
| Temperature in the chambers | Above normal or room temperature | Uneven (ice in the freezer, heat in the refrigerator) | High, motor hot |
| Behavior motor | It hums constantly, without turning off | It hums, there may be a quiet gurgling sound | It gets very hot, hums intermittently |
| Condenser (grid) | Cold or partially warm | Hot to the point of blockage, then cold | Very hot |
| Frost on the evaporator | Absent or weak | Abundant “scarf” or swelling of the wall | Absent |
Clogging of the capillary tube often occurs due to moisture in the system or oil breakdown products. In this case, the pressure at the outlet of the compressor increases, and at the inlet it decreases. A characteristic sign is swelling of the side wall of the refrigerator (where the perimeter heating circuit runs) or the formation of a “fur coat” in only one corner of the evaporator.
⚠️ Attention: It is impossible to independently eliminate leaks and blockages without special equipment (vacuum pump, pressure gauge station). A call to a technician is required for refilling and soldering.
Failures in the No Frost system and seal defects
In refrigerators Atlant with the system No Frost Continuous operation of the compressor may be caused by a malfunction of the defrost system. If the evaporator heating element is burnt out or the defrost timer is jammed, the evaporator becomes covered with ice. The air stops circulating, the temperature sensor does not see the cold and keeps the motor on.
You can check this by defrosting the refrigerator manually for 24 hours. If after defrosting the unit starts working in a normal cycle (turns on and off), then the problem is precisely ice freezing. It is necessary to check the heating element, thermal fuse and defrost sensor.
☑️ Checking the No Frost system
Do not forget about banal things. The rubber seal on the door dries out over time, cracks or comes away from the canvas. Warm air constantly enters the chamber through the cracks. The compressor tries to cool this flow and does not turn off. You can check the seal using a sheet of paper: hold it against the door and try to pull it out. If the sheet is pulled out without effort around the entire perimeter, the seal requires replacement or adjustment.
Incorrect installation may also be the cause. If the refrigerator is too close to the wall or heating radiators, heat exchange is disrupted. The minimum distance from the back wall to the wall should be 5-7 cm for free air circulation.
Faults of the electronic control module
Modern models Atlant equipped with electronic control units. If moisture gets on the board (condensation, leakage) or a power surge occurs, the compressor control relay may “stick” in the closed state. In this case, the compressor receives power constantly, ignoring sensor signals.
Diagnostics of the module requires special knowledge and equipment. Visually, traces of burning, swollen capacitors or oxidized traces may be visible on the board. If you do not have experience working with electronics, it is better not to climb inside the control unit, as you can aggravate the situation.
In some cases, the module may be working fine, but reading readings incorrectly due to a broken wiring. Check the integrity of the wires going to the temperature sensors and thermostat. Wires often break at bends or near door hinges.
When an urgent call to a technician is necessary
There are situations when self-repair is not only useless, but also dangerous. If you hear that the compressor is working, but at the same time it makes strange knocks, squeaks or whistles, turn off the device immediately. Further work will lead to complete destruction of the piston group.
Also, a master is needed if:
- 🛠️ You find oily spots under the refrigerator or at the place where the tubes are soldered (a sign of a leak).
- 🔥 The compressor body is hot to the point where it is painful to touch touch.
- 💨 There is a smell of burning or scorched wiring.
A professional technician will conduct a full diagnosis, check the pressure in the system, the compressor current consumption and the tightness of the circuit. This will allow you to accurately determine the cause and avoid unnecessary costs for replacing serviceable components.
Prevention and proper care of equipment
In order to Atlant refrigerator serve for a long time and not cause problems with continuous operation, it is important to follow the operating rules. Regularly (every six months) wash the back of the condenser to remove dust. The dust layer acts as a heat insulator, interfering with the cooling of freon, which makes the compressor work longer.
Keep the drainage hole in the fridge compartment clean. If it becomes clogged, water will stagnate, increasing humidity and stress on the defrost system. Do not place hot dishes in the chamber and do not load a large amount of warm food at once.
Regular checking of the condition of the seal and timely defrosting (for drip systems) will prolong the life of your unit. Remember that prevention is always cheaper and easier than major repairs.
Why does the refrigerator hum but does not turn off after defrosting?
If after complete defrosting (24 hours) the refrigerator continues to work without stopping, the problem is not a frozen evaporator. Most likely, the thermostat is faulty (does not open the circuit), a freon leak has occurred, or the compressor has lost performance. Diagnostics of tools is required.
Is it possible to operate the refrigerator if it does not turn off?
For a short time - it is possible, but not recommended. Long-term operation without a break leads to overheating of the motor windings, drying out of the oil and eventual jamming of the compressor. This also significantly increases energy consumption. It is better to eliminate the malfunction.
How much does it cost to replace a thermostat in an Atlant refrigerator?
The cost consists of the price of the part itself and the work of the technician. A mechanical thermostat is cheaper than an electronic sensor. It is better to check the exact price at service centers in your region, as it depends on the model of the refrigerator and the complexity of access to the unit.
What to do if, after replacing the freon, the refrigerator does not turn off again?
This may indicate poor quality work (moisture remains in the system, evacuation has not been done) or the presence of another malfunction that was not diagnosed initially (for example, faulty thermostat or insulation breakdown). A second call to the technician is required.