The situation when the refrigerator stops turning off while working non-stop often becomes an unpleasant surprise for the owner. At first, this may seem like a trifle, because the food is being cooled, and there is a cold inside, but you cannot ignore such work of the equipment. The constant hum of the motor and the continuous consumption of electricity are just the tip of the iceberg, behind which lies the risk of serious damage.
If the unit works without interruption, this means that the cooling system cannot reach the set temperature or the thermostat does not receive a signal that the cycle is completed. Compressor, which is the heart of the device, experiences colossal overloads, which inevitably leads to its overheating and premature failure. In this material, we will analyze in detail why the refrigerator does not turn off, which components are most often to blame for the problem, and what you can do yourself without calling a technician.
Natural causes and influence of the external environment
Before panicking and disassembling the equipment, it is worth eliminating external factors that often provoke failure work. Often the reason for endless work is a banal violation of operating conditions that users forget about. For example, if the refrigerator is installed too close to the heating radiators or direct sunlight falls on it, the sensors record high temperatures inside the chambers.
The control system, receiving false data, gives the command compressor to work harder to compensate for the heat gain. It is also worth checking whether the unit is loaded with hot products just brought from the store. In this case, the equipment will work until the entire volume cools down to the specified values.
⚠️ Attention: If you install the refrigerator in a niche without gaps for ventilation, heat exchange is disrupted. The rear grille must breathe, otherwise the motor will wear out.
Another important aspect is the tightness of the chambers. If the door does not fit tightly, warm air constantly flows inside. In response to this thermostat does not turn off the motor, trying to cool the incoming air. Check if anything is preventing the door from closing tightly, and make sure that the rubber seal is clean and elastic.
Problems with the thermostat and sensors
One of the most common reasons why the refrigerator does not turn off is a malfunction of the thermostat. This small device is responsible for monitoring the temperature inside the chambers and sending a signal to turn the compressor on or off. If the contacts inside the thermostat “stick” in the closed position, the circuit does not open, and the motor continues to run indefinitely.
Modern models with electronic control use temperature sensors (thermistors) instead of a mechanical thermostat. Their readings are transmitted to the control module. If the sensor fails and transmits low temperature values, the “brain” of the refrigerator will assume that it is warm inside and will not give a command to stop.
- 🔧 Mechanical wear: Over time, the thermostat contacts may oxidize or become deformed, which will lead to sticking.
- 🌡️ Displacement of the capillary tube: if the thermostat tube has moved, it is not in contact with the evaporator and does not read the temperature correctly.
- 💻 Electronics failure: in models with No Frost the sensor itself often fails or a failure occurs in the control board.
Diagnostics of the thermostat requires caution. In mechanical models, you can try to temporarily close the contacts coming from the thermostat, but this should only be done with the device disconnected from the network and understanding the risks. If after such manipulation the refrigerator works normally (it turns on and off), then the problem lies in the regulator.
Is it possible to drive with a faulty thermostat?
Technically, the refrigerator will work, but you risk freezing the food or, conversely, allowing it to spoil, since the cooling cycle will not be regulated automatically.
Wear of sealing rubber and violation of tightness
The tightness of the refrigeration chamber is the foundation for the proper operation of the entire system. The rubber seal located around the perimeter of the door loses its properties over time. It may become stiff, cracked or warped, especially in the corners. Through the resulting cracks, warm and humid air from the room constantly penetrates into the chamber.
Moisture settles on the evaporator, forming a thick “coat” of ice, which interferes with heat transfer. Sensors detect that the temperature does not drop to normal and force the compressor to work without stopping. Visually this may not be immediately noticeable, so it is worth conducting a thorough inspection.
| Symptom of malfunction | Probable cause | Consequences |
|---|---|---|
| The door does not fit completely | Deformation seal | Continuous operation of the motor |
| Ice at the entrance to the chamber | Ingress of warm air | Icing of the evaporator |
| The refrigerator is noisier than usual | Compressor overload | Reduced service life |
Replacing the seal is a procedure that you can do yourself if you find a suitable rubber model for your brand. It is also important to check the door hinges: if they are skewed, even a new seal will not provide a tight seal. Adjusting the hinges often solves the problem of a loose fit.
Malfunctions of the compressor and cooling system
If external factors and sensors are working properly, the problem may lie in the very “heart” of the refrigerator - the compressor. Over time, its performance decreases due to wear of the piston group or valves. The motor hums, trying to create the required pressure, but cannot pump the refrigerant with the required efficiency.
As a result, freon does not circulate throughout the system in full, and the temperature in the chambers does not reach the set values. The compressor works continuously, trying to compensate for its weak performance, but never receives a signal to rest from the thermostat.
- 🔨 Knocking or clanging: extraneous sounds during operation indicate mechanical destruction of the internal parts of the motor.
- 🔥 Overheating: if the compressor housing becomes hot to the point where it cannot be touched, this is a sign critical overload.
- 📉 Weak cooling: products in the refrigerator compartment may be lukewarm while the freezer is working hard.
Another reason may be a refrigerant leak. If a microcrack has formed in the system, freon gradually evaporates. The pressure drops and the compressor runs idle. In such cases, professional diagnostics using a leak detector and subsequent refilling of the system are required.
⚠️ Attention: An attempt to solder the tubes yourself or replace the compressor without evacuation of the system and refilling with freon is doomed to failure and can be dangerous.
Clogged capillary tube and problems with filter
In the refrigerant circulation system there are narrow sections - capillary tubes. They are sensitive to contaminants that can get inside the circuit during poor-quality repairs or due to destruction of internal components. The blockage prevents the normal flow of freon, creating a traffic jam.
The compressor begins to pump “to nowhere”, the pressure at the outlet increases, and at the inlet it drops. The refrigerator stops freezing, but the motor continues to hum. Often in such cases, you can notice that the condenser (grid at the back) heats up unevenly: one part is hot and the other is cold.
To eliminate the blockage, it is necessary to flush the system with nitrogen under pressure and replace the filter-drier. This is a complex technical procedure that requires special equipment. It is almost impossible to clean the capillary tube yourself at home without the risk of damaging other components.
Failures in the electronic control module
Modern refrigerators, especially models with the system No Frost and display are controlled by an electronic module. This is the “brain” of the device, which processes signals from all sensors and controls the actuators. If a failure occurs in the control board, it may simply not “see” the signal that the desired temperature has been reached.
The causes of failures can be different: power surges in the network, moisture, manufacturing defects or natural wear of elements. In such cases, the refrigerator may behave inappropriately: freeze until blocks of ice form or, conversely, not turn off, ignoring the readings of working sensors.
Diagnostics of the module requires knowledge in electronics and the use of a multimeter. Often repairs come down to resoldering burnt elements or completely replacing the board. If you notice that errors are flashing on the display or the indicators are blinking chaotically, the problem is most likely in the electronics.
☑️ Primary diagnostics of electronics
When you need to call a technician
Despite the desire to save money and repair equipment with your own hands, there are situations where professional intervention is inevitable. If you have checked the seal, defrosted the unit and made sure that the thermostat is working, but the problem has not disappeared, further self-diagnosis can be dangerous.
This is especially true for work related to refrigerant and live electrical parts. Unprofessional repairs can lead to permanent breakdown of expensive components or even a fire.
- 🛠️ Replacement of the compressor: requires welding, vacuuming and refilling with freon.
- 🔍 Search leaks: you need a special tool and a gas marker.
- 💳 Electronics repair: requires circuit knowledge and soldering equipment.
Remember that calling a technician in a timely manner is often cheaper than trying to revive a completely broken refrigerator after unqualified intervention. A professional will be able to accurately determine the cause and provide a guarantee for the work performed.
Frequently asked questions (FAQ)
How long can the refrigerator operate without interruption after being turned on?
After the first turn on or complete defrosting, the refrigerator may take from 2 to 12 hours to reach operating temperature. During this period, it may not turn off, and this is normal. If it works for more than a day without stopping, this is a sign of a malfunction.
Why does the refrigerator hum, but does not freeze or turn off?
This is a classic symptom of a freon leak or a serious blockage in the system. The compressor is running, but there is not enough refrigerant in the circuit to remove heat. You need to call a technician to find a leak and refill it.
Is it possible to use a refrigerator if it does not turn off, but freezes?
For a short time it is possible, but this is an emergency mode of operation. The compressor will quickly overheat and burn out. It is better to turn off the appliance and find the reason to avoid expensive repairs.
Does the temperature in the room affect the operation of the refrigerator?
Yes, if the room is too hot (above +30°C) or too cold (below +10°C), the refrigerator may not work correctly. In hot weather, it will work longer, trying to cool the chambers, and in cold weather it may not turn on at all or work intermittently.