The situation when the refrigerator does not turn offis one of the most common and alarming for the owner household appliances. The constant hum of the engine, the absence of pauses in operation and the freezing of ice on the walls are the first signals that the cooling system is out of normal mode. Ignoring this problem not only leads to a colossal increase in energy bills, but also creates the risk of complete breakdown of an expensive unit at the most inopportune moment.
In normal operation, the compressor turns on periodically, maintaining the set temperature, and then rests. If the rest cycle has disappeared and the motor hums for days on end, this means that heat transfer it is broken or the control electronics receives incorrect data. Understanding the physics of the process helps to quickly find the root of the evil, be it a banal door that is not tightly closed or a serious refrigerant leak.
Before calling a technician, it is important to conduct an initial diagnosis in order to exclude external factors that do not require complex repairs. Often the reason lies in little things that the user can fix on his own in a few minutes, saving the budget on calling a specialist. However, it is worth remembering that deep disassembly of components requires professional skills and tools.
Checking tightness and operating conditions
First of all, you need to make sure that the refrigerator is not trying to cool the entire apartment. If door seal it does not fit tightly, warm air constantly flows inside, forcing the compressor to work non-stop. Check the rubber cuff around the perimeter of the door: it should be clean, elastic and fit snugly to the body without gaps or cracks.
It is also worth paying attention to the location of the unit. If the refrigerator is located close to the wall or radiators, condenser on the back wall it cannot effectively transfer heat to the environment. This leads to overheating of the system and lack of shutdown cycles. The minimum distance from the back wall to the wall of the room should be at least 5-7 centimeters.
Another critical factor is the temperature of the food you load inside. Placing hot pots or large volumes of food at room temperature forces evaporator to work at the limit to compensate for the sudden increase in heat. In such cases, prolonged operation of the compressor is a normal reaction of the system, and not a breakdown.
Malfunctions of the thermostat and temperature sensors
One of the main reasons why the refrigerator does not turn offis the failure of the thermostat. This small device is responsible for monitoring the temperature inside the chambers and sending a signal to turn the motor on or off. If the contacts inside the thermostat are “stuck” in the closed position or it has lost sensitivity, the compressor will hum endlessly until it burns out.
In modern models with a system No Frost and electronic control, the function of a mechanical thermostat is performed by air sensors. They can transmit erroneous readings to the control board if their contacts are dirty or oxidized. The electronics “think” that the chamber is warm and does not give a command to stop the engine.
⚠️ Attention: Replacing the thermostat yourself requires disassembling the housing and working with electrical circuits. If you are not confident in your abilities, it is better to entrust this work to a professional to avoid a short circuit.
Thermostat diagnostics are often carried out by elimination or by direct replacement with a known-good element. In mechanical models, you can temporarily close the contacts of the thermostat: if after this the refrigerator starts working normally (turning on and off), then the problem is in the regulator. However, this is a temporary measure that requires the immediate purchase of a new part.
Refrigerant leak and problems with the compressor
If, during continuous operation of the motor, the refrigerator stops freezing or cools very weakly, most likely a problem occurred freon leak. The refrigerant circulates in a closed circuit, and if its seal is broken (for example, due to corrosion of tubes or mechanical damage), the pressure drops. The compressor tries to compensate for the lack of pressure, working without stopping, but does not provide the desired cold.
Itself compressor can also be the source of the problem. Wear of the piston group or valves means that the motor cannot gain the required pressure, even if the freon is in place. In this case, the unit hums, but does not turn off, trying to complete its task. Often, when a compressor breaks down, a characteristic metallic knock is heard or the hum becomes louder than usual.
To eliminate a leak, you need to find the location of the damage, solder the tubes and completely charge the system with new refrigerant. This is a complex technical procedure that requires special equipment such as a vacuum pump and a pressure gauge station. Attempts to simply “pump up” freon without eliminating the leak will only give a short-term effect.
| Symptom | Probable cause | Necessary actions |
|---|---|---|
| It hums, but does not freeze | Freon leak | Searching for leaks, soldering, refilling |
| Humming continuously, slightly freezing | Faulty compressor | Replacing the compressor |
| Works without stopping, freezes a lot | Thermostat is faulty | Replacing the thermostat |
| Humming, warm inside, no ice | Clogged capillary tube | Cleaning the system, replacing the filter |
Clogged capillary tube and condensate drainage system
Another technical reason the refrigerator does not turn offis clogged capillary tube. This is a thin element of the system through which the refrigerant enters the evaporator. If an ice plug forms in the tube or debris (oil breakdown products) gets in, the circulation of freon is disrupted. The pressure at the outlet of the compressor increases, and at the inlet it drops, which forces the motor to work in emergency mode.
Often the blockage is accompanied by unusual temperature behavior: the compressor may be hot, but the condenser (grid at the back) may be cold or only partially warm. In some cases, defrosting the refrigerator during the day with the doors open helps, which allows the ice plug to melt. However, if the cause is debris, professional cleaning with nitrogen will be required.
Why can’t you break through the blockage yourself?
Attempts to clean the capillary tube with wire or high pressure without experience often lead to rupture of thin-walled elements of the system or damage to the compressor, which makes repairs economically impractical.
Also It is worth checking the condensate drainage system, especially in models with a drip system. If the drain hole is clogged with crumbs or ice, the water will not drain, freezes, and can block the sensors or put a strain on the cooling system. Regular cleaning of the drainage prevents many problems with cyclic operation.
Failure of the electronics and control module
In modern refrigerators, such as Liebherr, Bosch or LG, the electronic control module is responsible for all processes. Power surges, moisture, or manufacturing defects can cause the board to glitch. In this case, the control signal to turn off the compressor is simply not received, although the temperature sensors may be working properly.
Signs of a problem with the electronics are often chaotic readings on the display, flashing indicators, or a complete lack of response to the control buttons. Sometimes a hard reset helps, which is done by unplugging the device for 15-20 minutes. If the problem returns after switching on, the board components may have failed.
Repairing the control module requires in-depth knowledge of radio engineering. Often it is not individual capacitors or relays that are replaced, but the entire board. It is important to use original spare parts or high-quality analogues, since incorrect operation of the electronics can quickly damage other components of the refrigerator, including an expensive compressor.
☑️ Diagnostics before calling a technician
Influence of external factors and mode “Super freezing”
Sometimes the reason for continuous operation lies not in a breakdown, but in an accidentally activated function. The "Super Freeze" (Super Freeze) mode is designed for quick freezing of large quantities of fresh food. In this mode, the refrigerator operates without shutting down for up to 24-48 hours, ignoring the thermostat readings in order to reduce the temperature as quickly as possible.
If you forget to turn off this function, the refrigerator will work in enhanced mode. Check the control panel: the snowflake indicator or the inscription “Super” will indicate that the forced freezing mode is active. The ambient temperature also affects the operation: in a hot room or in the kitchen in the summer, it is more difficult for the refrigerator to give off heat, and its operating time increases.
⚠️ Attention: Long-term operation in the “Super Freeze” mode with empty chambers can lead to freezing of food and unnecessary wear of the compressor. Use this mode only when necessary.
In addition, it is worth considering seasonality. In summer, when the room temperature reaches 25-30 degrees, the refrigerator takes more time to cool the condenser. During such periods, a reduction in the compressor rest time is a completely normal physical process, and not a malfunction.
When an urgent call to a technician is necessary
There are a number of symptoms in which further operation of the refrigerator becomes dangerous or pointless. If you hear a loud knock, grinding or squealing when the motor is running, this indicates mechanical destruction of the components compressor. Continuing to operate in this mode can lead to jamming of the engine and even fire of the wiring.
Also an alarming signal is the appearance of a burning smell or melted insulation. This indicates overheating of the electrical contacts, the start relay or the motor itself. In such a situation, you must immediately unplug the cord from the outlet and stop using the device until the malfunction is eliminated.
Do not delay repairs if you notice oil under the refrigerator or on the pipes at the back. This is a sign of depressurization of the system, which over time will lead to complete release of freon and combustion of the compressor due to lack of lubrication and cooling. Calling a specialist in a timely manner will save you money on purchasing a new unit.
Frequently asked questions (FAQ)
Can the refrigerator not turn off due to the heat in the room?
Yes, high ambient temperatures (above 30-32°C) make heat transfer difficult. The condenser does not have time to cool down, and the thermostat does not give the command to stop. In such cases, it is recommended to improve ventilation around the refrigerator or use air conditioning in the room.
How long should the compressor normally work?
Under normal conditions, the compressor works approximately 30-40% of the time (about 15-20 minutes it works, 30-40 rests). However, in summer or when the chambers are fully loaded, the operating time can increase to 50-60%. Continuous operation for more than 24 hours is considered an emergency.
Is it dangerous to leave a refrigerator that does not turn off turned on at night?
It is risky. If the cause is a freon leak or a compressor malfunction, it can overheat and burn out, creating the risk of a short circuit. If possible, it is better to turn off the device before the technician arrives.
Why does the new refrigerator work without interruption?
When you first turn it on or after complete defrosting, the refrigerator takes a lot of time (up to 10-12 hours) to cool the entire volume of chambers and food to the set temperature. During this period, continuous operation is normal. If it does not turn off even on the second day, this is a cause for concern.
Is it possible to replace the thermostat yourself?
Technically, this is possible if you have skills in working with electricity and tools. However, in modern models, access to the thermostat often requires complex disassembly. In addition, the correct setting of the new element is important, otherwise the temperature regime will be disrupted.