The situation when the refrigerator stops turning off and hums without interruption is familiar to many owners of household appliances. At first this seems like a small thing, but constant operation of the motor leads to serious consequences: overheating of components, increased electricity bills and, ultimately, breakdown of the unit. If you notice that your Indesit, Atlant or any other brand has gone into non-stop mode, you need to urgently look for the reason.
In this article we will look in detail at why the refrigerator does not turn off, how to independently carry out initial diagnostics and in which cases the intervention of a specialist will be required. Understanding the operating principles of compressor and the control system will help you save time and money, as well as keep food fresh.
Often users are faced with the fact that the equipment freezes properly, but there are no rest cycles. This is the first alarm bell. Normal operation suggests alternating periods of activity and rest. If the engine hums for hours, it means that the control system does not receive a signal that the required temperature inside the chambers has been reached.
Before you panic, it is worth assessing the situation objectively. Sometimes the reason lies in trivial things that are easy to fix with your own hands. However, ignoring the problem can lead to an expensive compressor compressor failing due to overload.
Natural causes of continuous operation
Continuous operation of the motor does not always indicate a breakdown. There are a number of external factors that force equipment to work in enhanced mode. In such cases, repairs are not required, it is enough to change the operating conditions.
The first and most common reason is high ambient temperature. If the refrigerator is standing near the radiator, in direct sunlight or in a hot kitchen, it is physically difficult for it to remove heat. Heat transfer is broken, and the unit is forced to work non-stop, trying to maintain the set temperature.
The second factor is a violation of the tightness or frequent opening of doors. Warm air from the room actively enters the chambers, sensors record the increase in temperature and command the compressor to work more intensely. It is also worth checking super freezing mode: if you accidentally activated this function, the refrigerator will work continuously until you turn it off.
⚠️ Attention: Installing the refrigerator closer than 5-10 cm from the wall or heating devices critically disrupts air circulation, which leads to overheating condenser.
The third point is loading warm products. If you put a freshly cooked hot dish into the chamber or defrosted meat at room temperature, the system will require a lot of time and energy to cool the volume.
- 🔥 Location of equipment near heat sources (stove, radiator, window on the sunny side).
- 🚪 A door that is not tightly closed or a damaged seal that allows warm heat to pass through air.
- ❄️ Activated “Super Freeze” or “Quick Cooling” mode.
- 🍲 Loading a large amount of warm food at the same time.
Malfunctions of the thermostat and sensors
If external factors are excluded, most likely the problem lies in the electronics or control mechanics. The main task thermostat (thermostat) is to monitor the temperature inside the chamber and open the compressor power circuit when the set values are reached. If this unit fails, the shutdown signal simply does not arrive.
In mechanical models, the thermostat is a device with a bellows filled with freon and a contact group. Over time, the contacts may “stick” in the closed position, or the bellows may lose its seal. As a result, the refrigerator “thinks” that it is still warm inside and continues to freeze.
In modern models with a system No Frost and electronic control temperature sensors (thermistors) are responsible for the temperature. They transmit data to the control module. If the sensor “lies” or breaks, the module does not see the real picture and keeps the compressor on. Often, when a sensor breaks down, an error code lights up on the display, but not always.
Diagnostics of the thermostat in mechanical refrigerators (for example, old ZIL or Biryusa) is possible at home. You can test it with a multimeter or temporarily close the contacts to check the start of the compressor. However, replacing sensors in electronic systems often requires disassembling the housing and the presence of special tools.
How to check the thermostat yourself?
To check a mechanical thermostat, you need to remove it, lower the sensitive tube into cold water with ice and ring the contacts. If there is no click or break in the circuit, the part is faulty. However, in modern models, access to the thermostat is difficult, and it is better to entrust this to professionals.
Refrigerant problems: freon leak
One of the most insidious reasons why the refrigerator does not turn off is a leak refrigerant (freon). It would seem that if there is little gas, the refrigerator should freeze worse and turn off more often. But the opposite happens: due to a lack of freon, the pressure in the system drops, and the compressor cannot gain the necessary pressure to shut down.
The control system “sees” that the temperature in the chamber does not drop to normal (since the cooling capacity has dropped), and keeps the motor on around the clock. As a result, the compressor wears out, gets very hot, and the products gradually deteriorate.
Leakage can occur in places where tubes are soldered, in the evaporator (especially if it was damaged with a knife during defrosting) or in the condenser due to corrosion. It is difficult to determine a leak visually; this often requires special equipment - a leak detector. A characteristic sign may be swelling of the back wall inside the freezer or the appearance of oily spots under the refrigerator.
⚠️ Attention: Filling the refrigerator yourself with freon without vacuuming the system and looking for leaks is a pointless waste of money. The gas will leave again after a short time.
If you notice that the refrigerator is humming, but not freezing (or freezing very weakly), and does not turn off, there is a 90% probability that this is a leak. In this case, it is necessary to block access to the equipment and call a technician to find the location of the circuit damage.
Clogged capillary tube
Another technical malfunction leading to continuous operation is clogged capillary tube. This is a thin copper pipeline in which throttling (a sharp drop in pressure) of the refrigerant occurs. If a plug forms inside the tube from wear products of oil or moisture, the circulation of freon is disrupted.
The compressor tries to push the refrigerant while running idle. The pressure at the outlet of the compressor increases, and freon does not enter the evaporator in the required volume. Sensors detect the absence of cold and do not give a command to stop. Symptoms of a blockage are often:
- 🔊 Loud, intense humming from the compressor.
- 🌡️ Hot condenser (grid at the back) only at the top or near the motor.
- ❄️ The evaporator inside the chamber remains warm or covered frost unevenly.
To eliminate this problem, professional cleaning of the system with nitrogen under pressure, replacement of the filter-drier and subsequent refilling with freon is required. It is impossible to carry out this work independently without a vacuum pump and a pressure gauge station.
Compressor wear and loss of performance
The most expensive scenario is wear itself compressor. This is the “heart” of the refrigerator. Over time, the piston group wears out, the valves lose their tightness, and the motor ceases to create the necessary pressure. It works constantly, trying to compensate for its weak performance, but in fact it simply circulates gas in a circle without effective cooling.
The loss of performance can be determined by the temperature of the compressor housing and tubes. If the motor is hot to the point that it is impossible to touch it, and the outlet tubes are warm, but not hot, the resource of the unit is running out. Also a sign may be difficult starting: the compressor hums, the relay clicks, but cannot start or works intermittently.
In modern inverter models (for example, LG, Samsung), diagnostics are more difficult. There, the inverter module is responsible for the operation of the motor. If it fails, the compressor may work chaotically or not develop the required speed, which the system perceives as a lack of temperature.
| Symptom | Probable cause | Difficulty of repair |
|---|---|---|
| Humming, does not freeze, does not turns off | Freon leak | Medium (requires equipment) |
| Humming, weak freezing, works non-stop | Capillary clogged | High (purge required) |
| Works constantly, too cold inside | Thermostat/sensor is faulty | Low/Medium |
| The engine gets very hot, the hum is quiet | Compressor wear | High (replacement of unit) |
Self-diagnosis algorithm
Before calling the service, try to carry out an initial diagnosis. This will help you more accurately describe the problem to the technician or, perhaps, resolve the issue yourself. Start with a visual inspection and simple manipulations.
Check the tightness of the door. Take a sheet of paper, clamp it with the door and try to pull it out. If the sheet is removed easily without resistance along the entire length of the seal, the door does not close tightly. Also make sure that the refrigerator is level and not tilted back.
☑️ Initial check of the refrigerator
If everything is in order with the door and settings, listen to the sounds. A steady hum is normal. A knocking, grinding or intermittent humming sound indicates mechanical problems. Check the temperature of different areas: if the freezer is cold and the main compartment is warm, but the motor does not stop, this is a clear sign of a leak or blockage.
It is important to remember the features of operation in different seasons. In winter, if the refrigerator is placed on an unheated balcony or in a cold corridor, the oil in the compressor may thicken. In such cases, startup may be difficult and operation may not be correct.
⚠️ Attention: Specifications and ambient temperature requirements may vary among different manufacturers. Always check the instructions (data sheet) for your specific model, section “Operation”, before installing equipment in non-standard conditions.
Frequently asked questions (FAQ)
How long should the refrigerator operate normally?
In normal mode, the refrigerator operates cyclically: it runs for about 15-20 minutes and Rest for 20-40 minutes. The working time ratio is about 40-50%. If the unit operates more than 70% of the time without breaks, this is a cause for concern.
Can the refrigerator not turn off due to the heat in the summer?
Yes, in extreme heat (above +30°C), the compressor operating time increases and the rest time is reduced. However, even in summer it must be turned off periodically. If it hums for days, it means that the heat dissipation is broken or there is a malfunction.
What will happen if the cause of continuous operation is not eliminated?
Prolonged operation without rest will lead to overheating of the compressor windings, drying out of the oil and, ultimately, to the wedge of the motor. Repair in this case will cost much more than timely repair of the leak or replacement of the sensor.
Why did the new refrigerator immediately start working without turning off?
When first loading or after defrosting, the refrigerator takes a long time (up to 24 hours) to gain temperature. During this period, it can work almost non-stop. If it is new, empty and cool, but does not turn off, this is a defect.
How to extend the life of a compressor?
Do not place hot foods, keep the condenser clean at the back (dust impairs heat transfer), do not open the door unnecessarily and ensure a gap between the back wall and the wall of the room is at least 10 cm.