The situation when the refrigerator works without interruptionsis one of the most alarming signals for the owner of household appliances. In normal mode, the unit should cyclically gain cold and turn off to rest the motor. If the compressor hums continuously, this not only leads to a sharp jump in electricity bills, but also creates a real threat of failure of expensive components.
There can be many reasons for this behavior: from a banal clogged ventilation grille to a complex refrigerant leak. Modern models with a No Frost system and inverter compressors may behave differently than classic two-chamber refrigerators, so it is important to be able to distinguish between normal and pathological. Often, owners notice the problem too late, when food has already begun to freeze or, conversely, deteriorate due to insufficient cooling.
In this article we will analyze in detail the mechanics of the process, explain why thermostat it can “stick”, and how to determine that it is time to call a technician. Ignoring the first signs of continuous engine operation often leads to the need to completely replace the compressor, which is not economically feasible.
⚠️ Attention: If you smell burning or see sparking in the compressor area, immediately unplug the device and do not try to start it again.
Operation mechanics: why it should turn off
The operating principle of any refrigeration unit is based on circulation refrigerant (of freon) in a closed loop. The compressor compresses the gas, turning it into a liquid, which, passing through the capillary tube and evaporator, boils and absorbs heat from the chambers. As soon as the temperature inside reaches the set value, thermostat opens the electrical circuit, stopping the motor.
If this cycle is disrupted, the refrigerator goes into “perpetual motion” mode. This occurs when the temperature sensor does not receive the correct signal that cold has already accumulated. Or the cold goes away faster than it has time to accumulate, forcing the system to work at its limit. Inverter compressors In such cases, they may not stop completely, but only reduce the speed, but classic models should click and die down.
A constant load leads to overheating of the motor windings and loss of lubricating properties of oil. As a result, the resource of a node designed for 10 years can be exhausted within a few months of continuous operation. Understanding that cyclicality is the basis of the life of a refrigerator helps you quickly respond to failures.
External factors and operating errors
Before looking for complex breakdowns inside the unit, it is worth eliminating external factors. Often the reason lies in improper installation or maintenance. If condenser (the grille at the back) is covered with a layer of dust and pet hair, heat transfer is disrupted. The motor tries to compensate for poor (heat transfer) by increasing the operating time.
Another common mistake is installing the refrigerator too close to the wall or heating appliances. For normal air circulation, a gap of at least 5-7 cm is required. If you have just defrosted the unit or loaded a large amount of warm food into it, it will work longer than usual, but should still turn off.
- ❄️ Check the tightness of the fit sealing rubber to the body - even the gap lets in warm air.
- 🌡️ Make sure that the thermostat is not set to the maximum value unnecessarily.
- 🧊 Do not place hot pots inside - this is a direct way to overload the compressor.
Particular attention should be paid doors. If magnetic valve the door is weakened or skewed, the tightness is broken. Warm air constantly flows inside, sensors record the temperature rise and do not allow the engine to rest. This is a classic example when the equipment is in working order, but is operated incorrectly.
Malfunctions of the thermostat and sensors
The most common technical reason for continuous operation is failure of thermostats (thermostat). This small device is responsible for turning the compressor on and off. If its contacts are “stuck” in the closed position or the sensitive tube has burst, the shutdown signal simply does not arrive. In electronic models temperature sensors (NTC thermistors) are responsible for this, which can give false readings.
Diagnostics of a mechanical thermostat is relatively simple: it can be temporarily replaced or “ringed” with a multimeter. If the click does not occur when the sensor is cooled (for example, in the freezer), the part requires replacement. In electronic systems, the error is often displayed on the display in the form fault code, which can be found in the instructions.
It is also worth checking defrost sensor in No Frost systems. If he “lies” and tells the control unit that the evaporator is warm, the refrigerator will try to cool the chamber indefinitely. Repair in this case requires disassembling the internal panel of the freezer.
Problems with sealing and tightness
Sealing rubber is the first barrier to warm air. Over time, it loses elasticity, cracks or moves away from the body. If you notice that the door does not close tightlyor you can pass a sheet of paper through the gap without resistance, then the seal is broken. The refrigerator will work constantly, trying to cool the entire room.
Sometimes the problem is solved by simple washing and lubrication with silicone. However, if the rubber is deformed or torn, it will need to be replaced. In some models the seal is glued, in others it is fixed in a special groove. It is important to choose an original spare part or a high-quality analogue, since universal solutions often do not provide the required density.
| Symptom | Probable cause | Test method |
|---|---|---|
| The door does not stick | Contamination or distortion | Visual inspection and test with a sheet of paper |
| Rubber is sticky or hard | Material aging | Tactile elasticity test |
| Visible breaks | Mechanical damage | Careful inspection around the perimeter |
| Condensation at the end of the door | Poor fit | Checking the door angle |
⚠️ Attention: An attempt to restore an old, “dull” seal with boiling water gives only a temporary effect. In a couple of weeks the problem will return, so it is better to immediately replace the part.
Freon leakage and system blockage
If the refrigerator hums, but does not cool (or cools very little), and does not turn off, there is a high probability refrigerant leaks. Freon could leak through a microcrack in the evaporator (often due to corrosion or careless defrosting with a knife). The compressor runs idle, trying to build up pressure that is not there.
Another option is capillary blockage. Oil breakdown products or moisture freeze in the narrow tube, blocking circulation. In this case, the motor also works without stopping, trying to push through the plug. Both cases require the intervention of a specialist with equipment for vacuuming and refilling the system.
Is it possible to refill freon yourself?
Self-refueling is impossible and dangerous. Special equipment is required for pumping out air, finding leaks and dosing refrigerant. Trying to “just add gas” without eliminating the leak will result in a second breakdown in a short time.
A symptom of a leak is often a hot condenser (grid at the back) only halfway hot or the absence of a characteristic hiss when punctured. It is impossible to fix such a malfunction on your own; you need to call a specialist.
Wear of the compressor and start relay
When all the sensors are in working order, and the freon is in place, but the motor does not stop, the problem may be in the very “heart” of the unit. Compressor it may lose its performance due to the exhaustion of the piston group. It hums, but does not create the required pressure in the system. The control unit “sees” that the temperature does not drop and does not give a command to turn off.
Also often fails starting relay. If its contacts burn or stick, it may not break the circuit after the engine starts. As a result, the motor runs continuously, which leads to its rapid overheating and eventual combustion. Replacing the relay is an inexpensive and quick procedure.
☑️ Compressor diagnostics
It is important to distinguish between a noisy but working motor and a unit that really requires replacement. If the compressor has been operating for more than 10 years and has begun to behave strangely, it is often more profitable to replace the entire unit than to repair it many times.
Specifics of operation of modern models
Owners of new refrigerators with technology Full No Frost or Total No Frost may panic ahead of time. These models can actually work longer than older counterparts, as they maintain a more stable temperature. However, they must also stop periodically.
There is the concept of a “fresh zone” or “zero chamber”, where the temperature is maintained around 0°C. If you have set the minimum temperature in the main chamber, and the apartment is hot, the refrigerator can operate almost continuously. This is not a breakdown, but a feature of operation in extreme conditions.
However, if you notice that the unit does not turn off for days, and the products in the main chamber turn into ice, this is a clear sign of a malfunction control unit or the sensors. The electronics could “glitch” and fix the constant freezing mode.
Frequently asked questions (FAQ)
How long should the refrigerator work before the first shutdown?
Usually the first cycle after turning on an empty refrigerator takes from 30 minutes to 2 hours, depending on the volume chambers and ambient temperature. If after 3-4 hours the motor does not click and stop, this is a sign of a problem.
Is it dangerous to leave a refrigerator running without interruption?
Yes, it is dangerous. Long-term operation without rest cycles leads to overheating of the compressor windings, solidification of the oil and eventual jamming of the piston group. This can lead to a fire or complete failure of the equipment.
Can the refrigerator not turn off due to the heat in the room?
High room temperature (above +30°C) increases the load on the unit, and it can work longer. However, it should still turn off periodically, albeit for short periods of time. If there are no pauses at all, look for a malfunction.
Why doesn’t the refrigerator turn off for a long time after defrosting?
After defrosting, it’s warm inside, so the motor works in increased mode to gain temperature. This is fine. But if, 5-6 hours after turning it on, it continues to hum without stopping, perhaps you did not close the door tightly or damaged the system when cleaning.