The situation when the refrigerator stops turning off and hums without interruption causes panic among many owners. It would seem that the equipment simply works more intensely, but in fact this is a signal of a serious failure in the thermoregulation system or the tightness of the circuit. Constant operation of the compressor is not only a high electricity bill, but also a direct path to overheating of the motor and its complete failure in the very near future.
If you notice that the pauses between cooling cycles have disappeared, and the unit is wearing out, you need to act immediately. Unlike other breakdowns, here the count can go on for hours. Long-term operation without rest for a compressor is equivalent to a marathon without a finish line: sooner or later the resource will be exhausted, and repairs will cost much more than timely diagnosis.
In this article we will analyze the main technical reasons why the refrigerator does not turns off, and we will help you determine whether you can solve the problem yourself or whether you need to call a technician. You will learn how to distinguish simple overheating from a freon leak or sensor failure.
Seal failure and refrigerant leak
One of the most common reasons for continuous operation is freon leak (refrigerant). In good condition, the gas circulates in a closed circuit, taking heat from the chambers and transferring it to the condenser. If a microscopic crack appears in the tubes or joints, the pressure drops, and the compressor tries to compensate for the lack of cold by running idle.
It can be difficult to detect a leak on your own, since the refrigerant often has no odor. However, there are indirect signs:
- ❄️ The rear wall of the refrigerator compartment is no longer covered with uniform frost.
- 🔥 The condenser (grid at the back) remains cold or barely warm, although the motor is hot.
- 📉 The food in the main chamber begins to thaw, despite the humming of the unit.
If the system has lost its tightness, simply refilling the gas will not help - you need to look for the leak and seal it. In models with the No Frost system, leakage often occurs in the foamed part of the case (evaporator), which requires complex repairs with replacement of the evaporator. An attempt to simply add gas can lead to repeated failure in a few days.
⚠️ Attention: Freon can be dangerous if inhaled in high concentrations. If you smell a strange chemical smell near a running refrigerator, immediately ventilate the room and unplug the appliance.
Malfunction of the thermostat or temperature sensor
The second most common culprit is thermostat (thermostat) or electronic temperature sensor. It is these elements that give the command to “stop” the compressor when the set temperature is reached in the chamber. If the thermostat is “stuck” in the “on” position or the sensor transmits incorrect data to the control module, the refrigerator will freeze until the bitter end.
In older mechanically controlled models, the thermostat is a capillary tube with gas inside. Over time, the gas may evaporate or the contacts may oxidize. In modern models with electronics, the problem lies in the sensoritself. You can check a mechanical thermostat by closing the contacts directly: if the refrigerator starts working and turns off (when manually opened), then the problem is in the sensor.
Symptoms of a breakdown of the thermoregulatory system often include:
- 🌡️ Temperature in the chamber falls below the set value (food freezes).
- 🔌 The device does not respond to turns of the temperature control knob.
- 💡 The indicators on the panel may show an error or light constantly.
Problems with the seal and thermal insulation
Often the reason lies not inside, and outside - in violation of thermal insulation. If rubber seal the door does not fit tightly, warm air from the room constantly enters the chamber. Sensors detect an increase in temperature and force the compressor to work without stopping, trying to cool the incoming heat.
Check the condition of the cuff around the perimeter of the door. The rubber could dry out, crack, or simply become contaminated with grease, which is why the magnetic tape no longer adheres tightly to the metal of the case. The door may also warp due to loose hinges or too heavy contents on the shelves.
Perform a simple test with a sheet of paper:
- Press a sheet of paper between the door and the refrigerator body.
- Try to pull the sheet out without opening the door.
- If the paper is pulled out easily and without resistance - the seal is broken.
Clogged capillary tube and compressor malfunction
More complex technical problems are associated with capillary tube the motor itself. The freon circulation system may become clogged due to oxidation products, moisture or debris. This creates a “plug” that prevents the normal flow of refrigerant. The compressor tries to push gas, works with increased load and overheats, but cannot turn off because the required temperature is not reached.
The compressor itself may also be faulty. Wear of the piston group or valves leads to a drop in performance. The motor hums and vibrates, but does not create enough pressure. In this case, it works constantly, trying to compensate for its weakness, which often ends in heat stroke and shutdown.
Diagnostics of these components requires special equipment:
- 🔧 Pressure gauge to check the pressure in the circuit.
- 🔨 Vibration test to evaluate the operation of the motor.
- 🌡️ Thermal imager or probe for searching for temperature differences in the tubes.
⚠️ Attention: Do not try to open the circuit yourself or solder the tubes without a vacuum pump and skills. The entry of moisture or air into the system is fatal for the refrigerator.
Why is the compressor hot, but does not turn off?
If the compressor is very hot (it is impossible to hold your hand), this is a sign of overload. The thermal relay should turn it off, but if it's faulty the motor will burn out. A common case is an interturn short circuit of the windings, when the motor consumes a current higher than normal, but does not develop power.
Operating errors and external factors
Before sounding the alarm and calling a technician, it is worth eliminating trivial operating errors. Sometimes the refrigerator does not turn off because you yourself have created unbearable conditions for it. For example, installing the device too close to a wall, a heating radiator, or in direct sunlight disrupts heat transfer.
Also critically affects operation room temperature. If the kitchen is +30°C or higher, a standard refrigerator may simply not cope with heat removal and go into constant operation. Most household models are designed for climate class SN-T (from +10 to +38°C), but in hot weather their efficiency drops.
Check the following points:
- 🍲 Have you placed hot pots or a large amount of warm water in the chamber? products?
- 🚪 Was the door left open for a long time?
- ❄️ Is the “Super Freeze” mode (button with a snowflake) turned on, which disables automatic shutdown?
☑️ Diagnostics before the call technicians
Diagnostic table: symptom - probable cause
To simplify troubleshooting, use the summary table. It will help you navigate the nature of the breakdown based on external signs.
| Symptom | Probable cause | Difficulty of repair |
|---|---|---|
| Humming, but no cold | Freon leak or blockage | High (needs a technician) |
| Freezing too much | Thermostat/sensor is faulty | Medium (sensor replacement) |
| Buzzing intermittently, very hot | Compressor wear | High (motor replacement) |
| Works constantly, cools normally | Door seal failure | Low (adjustment/replacement) |
| Clicks and does not start/does not lock | Start relay or thermal relay | Medium (relay replacement) |
It is important to understand that diagnostics is only the first step. Even if you determine that the problem is in the thermostat, replacing it in some models (for example Indesit or Atlant) requires partial defrosting and access to hidden elements.
What to do if the refrigerator does not turn off: algorithm of actions
If you are faced with the problem described problem, do not expect complete failure of the equipment. Follow the algorithm: first simple checks, then complex ones. First, defrost the refrigerator completely. Leave it turned off for 12-24 hours. This is necessary so that all the ice that could block the sensors or tubes evaporates.
After defrosting, turn on the device. If it worked for several hours, reached the temperature and turned off, the problem was freezing (often happens in the No Frost system when the defrost heating element malfunctions). If the situation repeats after a day, technical intervention is required.
When calling a technician, be sure to inform:
- The model and year of manufacture of the refrigerator.
- How long ago the problem began (sharply or gradually).
- Are there any extraneous sounds (gurgling, clicking, whistling).
- Has the temperature in the room changed recently.
⚠️ Attention: Technical characteristics and location of components may vary depending on the manufacturer and year of manufacture. Always check the official instructions for your model before disassembling.
Can the refrigerator not turn off due to power surges?
Yes, unstable voltage in the network can damage the start relay or electronic control board. In this case, the relay may “stick” in the closed state, supplying power to the compressor constantly. It is recommended to use a voltage stabilizer or surge protector to protect equipment.
How long can a refrigerator operate without stopping before breaking down?
Critical time is considered to be operation without a break for more than 12-24 hours. After this period, the risk of overheating of the windings and jamming of the piston group increases exponentially. If the refrigerator is humming for the second day, turn it off to avoid a fire or expensive repairs.
Why doesn’t the new refrigerator turn off immediately?
After the first turn on or long-term defrosting, the refrigerator requires time (from 2 to 8 hours) to cool the entire volume of chambers and food to the set temperature. During this period, it can work continuously - this is the normal “first start” mode, and not a breakdown.
Does the number of products affect the operating time?
Yes, fully loading the chambers requires more time and energy for cooling. However, if the refrigerator is 10-15% full, it should turn off more often. An empty refrigerator turns off faster, since the volume of air for cooling is less than the volume of solid products.