The situation when Indesit refrigerator with the system No Frost stops turning off is an alarming signal for any owner of household appliances. A compressor operating in continuous mode without rest breaks is subjected to enormous loads, which can lead to its complete combustion in the shortest possible time. The owner notices that the unit is humming around the clock, the temperature inside the chambers drops below the permissible minimum, and excess ice forms on the walls, despite the declared defrosting technology.
Why does motor-compressor not receive commands to stop? Most often, the problem lies in a violation of heat exchange or failure of control system elements. In units Indesit with the function No Frost electronics must accurately read the temperature of the evaporator and air in the chamber, but if the sensors lie or the refrigerant is gone, the cooling cycle is not interrupted.
It is important to understand that ignoring this symptom leads not only to an increase in electricity bills, but also to damage to food due to freezing. The critical point is that with continuous operation for more than 24 hours, the life of the compressor is reduced significantly, and repairs may require replacing the most expensive unit of the refrigerator. Therefore, it is necessary to promptly identify the cause of the failure.
Malfunction of the thermostat or temperature sensor
The most common reason why Indesit refrigerator does not turn off is the failure of the thermostat. In mechanical models, it is this element that is responsible for temperature control, which physically opens the circuit when the specified parameters are reached. If the contacts inside the thermostat are “stuck” in the closed position, the compressor will work indefinitely until you forcibly disconnect the device from the network.
In more modern models Indesit No Frost with electronic control, the thermostat function is performed by a temperature sensor (thermistor). It transmits signals to the control module, which, in turn, commands the compressor. Sensor malfunction or a break in its wiring leads to the fact that the “brain” of the refrigerator receives false data that the chamber is still warm and continues to circulate refrigerant.
⚠️ Attention: Trying to independently replace the thermostat in electronically controlled refrigerators without first diagnosing it with a multimeter can lead to installing the wrong part and aggravating the problem.
Diagnostics of the thermostat in mechanical models is often carried out by the method of elimination. If, when turning the control knob to the “0” or “Off” position, the compressor stops, but in any other position continues to work even at a clearly low temperature, it falls on the thermostat. In electronic models sensor failure often accompanied by blinking indicators on the control panel, which simplifies troubleshooting.
How to check the thermostat with a multimeter?
To check a mechanical thermostat, you need to remove it, immerse the sensitive tube in cold water with ice and call your contacts. If the circuit does not open during cooling, the part is faulty.
Refrigerant leakage and violation of system tightness
One of the most insidious problems, due to which Indesit refrigerator works without stopping, is a freon leak. It would seem that logic dictates that if there is a shortage of gas, there should be less cold, but in systems No Frost everything is more complicated. When the pressure in the circuit decreases, the compressor cannot reach the required condensation temperature and simply does not reach the shutdown point inherent in the operating algorithm.
As a result, the unit hums for days, trying to “catch up” the temperature, but due to the small amount of refrigerant, the heat capacity of the system drops. Freon leak can occur through microcracks in the evaporator, in places where tubes are soldered, or through a manufacturing defect. This happens especially often if the evaporator is made of aluminum and has undergone corrosion or mechanical damage during defrosting.
- 🔍 The compressor works constantly, but the cold in the chambers is weak or absent at all.
- 🔍 On the rear radiator grille (condenser), the temperature is distributed unevenly: part is hot, part is cold.
- 🔍 Oily spots may be observed in the area of the leak, as freon circulates along with the compressor oil.
If you suspect refrigerant leakage, you need to call a technician to carry out pressure testing of the system with nitrogen. Finding the leak and refilling the refrigerator yourself is technically difficult and dangerous without special equipment. Prolonged operation of the compressor “dry” or with low oil pressure can lead to jamming of the piston group.
Problems with the No Frost defrost system
Refrigerators Indesit No Frost are equipped with an automatic defrost system for the evaporator, hidden behind the back wall of the freezer. If this system fails, a “coat of ice” begins to grow on the evaporator. This ice shell blocks the circulation of cold air and, more importantly, interferes with the correct operation of the defrost sensor.
In normal mode, after a certain number of compressor operating cycles, the defrost heating element turns on, which melts the ice. Three key elements are responsible for this process: Evaporator heating element, a defrost timer (or electronic module) and a defrost sensor. If the heating element is burned out, the ice does not melt, accumulates and begins to interfere with the operation of the fan and temperature sensors.
The defrost sensor can “lie” to the control module, reporting that the defrosting process is still in progress or, conversely, that the evaporator is too hot, which is why the cooling cycle does not complete correctly. As a result, compressor is forced to work in enhanced mode, trying to compensate for poor heat transfer through the ice layer.
| System element | Function | Fault symptom |
|---|---|---|
| Defrost heating element | Heating the evaporator to melt ice | Ice build-up on the evaporator, no heating when turned on |
| Defrost sensor | Temperature control evaporator | Circuit malfunction, no signal to module |
| Timer/Module | Switching cold/defrost modes | The refrigerator does not go into defrost mode at all |
| Fan | Air circulation | Freezing of the blades, lack of airflow in the chambers |
For diagnostics, you need to defrost the refrigerator manually for 10-12 hours. If, after complete defrosting and turning on, the unit started working normally (turned on and off cyclically), then the problem is definitely in the system No Frost. If after a couple of days the situation repeats, the burnt heating element or sensor needs to be replaced.
Compressor wear and problems with the motor
In itself compressor can also cause continuous operation, although this is more often a consequence of other problems or natural aging. Over time, the mechanical parts of the motor wear out, compression drops, and the unit is simply unable to create the necessary pressure to achieve the set temperature. Trying to compensate for the loss of efficiency, it works without interruption.
Another reason may be a malfunction of the start-up relay. This small element is responsible for starting the engine and protecting against overloads. If the relay is stuck or not working correctly, it may not open the circuit even when the thermostat commands to stop. In such cases, a characteristic click is often heard, but the engine does not stop.
Signs of problems with motor-compressor are:
- 🔥 Strong heating of the compressor housing (impossible to touch with your hand).
- 🔊 Change in operating sound: the appearance of a metallic knock, hum or vibration.
- 📉 Reduced performance: the refrigerator works, but does not freeze properly.
⚠️ Attention: If the compressor runs continuously and gets very hot, there is a risk of it catching fire or melting the wiring. Immediately disconnect the device from the power supply if a burning smell appears.
The compressor cannot be repaired at home - it must be completely replaced. This is a labor-intensive process that requires evacuation of the system and charging with freon, so it is performed only in service centers. However, if the problem is in the relay, replacing it is a matter of a few minutes and minimal costs.
The influence of external factors and improper operation
Before committing a breakdown, it is worth eliminating environmental factors. Indesit refrigerator, like any other equipment, is sensitive to operating conditions. If the unit is installed close to the wall, in a niche without ventilation or next to heating devices, the heat transfer of the condenser is disrupted.
In the hot season or with high humidity in the room, the load on the cooling system increases many times over. The compressor may run longer than usual trying to reach the temperature, but normally it should still turn off. If the room is +30°C, and the refrigerator is near the radiator, it can work almost non-stop, which is an emergency mode for it.
It is also worth checking the tightness of the door. If the sealing rubber is worn out, dirty or the door is warped, warm air constantly enters the chamber. The sensor detects an increase in temperature and does not give a command to stop the compressor. Frequently opening the door or loading hot products also leads to prolonged operation of the motor.
☑️ Checking the operating conditions
Failures in the electronic module control
In modern models Indesit with a display and many functions, electronic control moduleis responsible for all processes. This is the “brain” of the refrigerator, which processes signals from all sensors. If a track on the control board burns out, a capacitor fails, or a software failure occurs, the command to turn off the compressor may simply not be received.
Often such breakdowns occur after power surges in the network. Even if there are visually no traces of burning on the board, it can produce erroneous signals. In such cases, the refrigerator may behave chaotically: it may not turn off, it will not turn on, or it will show the wrong temperature on the display.
Diagnostics of the module requires special knowledge and equipment. The master checks for the presence of control signals at the output of the board. If the thermostat is working, the freon is normal, the defrosting system is intact, and the compressor is humming non-stop - most likely the problem lies in the control unit. You can try to reflash or repair it, but more often replacement is required. control unit. You can try to reflash or repair it, but more often it requires replacement.
Frequently asked questions (FAQ)
How long should an Indesit refrigerator compressor normally operate?
In normal operation, the cycle is approximately: 10-15 minutes of operation and 20-30 minutes of rest. The work efficiency usually does not exceed 40-50%. If the refrigerator runs for more than 20 minutes without a break in an empty state, this is a cause for concern.
Is it possible to operate the refrigerator if it does not turn off?
For a short time - yes, so that the food does not go missing while you are waiting for the technician. But long-term operation in this mode (more than 24 hours) is guaranteed to lead to compressor failure. It is better to temporarily transfer the food to another place and turn off the unit.
Why did the refrigerator start working without stopping after defrosting?
Perhaps the temperature sensor or defrost heating element was damaged during defrosting. Freon could also leak due to corrosion that appeared after the ice was removed. The third option is that you forgot to close the door tightly or set the “Super Freeze” mode.
What should you do if the refrigerator hums, but does not freeze or turn off?
This is a classic sign of a freon leak or a clogged capillary system. It is urgent to disconnect the device from the network, defrost it and call a specialist to look for leaks and refill it.
Can the “Super Freeze” mode cause continuous operation?
Yes, in some Indesit models, with the Super Freeze function enabled, the compressor can work continuously for up to 72 hours or until you forcibly turn off this mode. Check the control panel.