The situation when the refrigerator hums without interruption frightens many owners. It seems that the equipment is about to fail or has already broken down. However, continuous operation of the compressor does not always mean fatal failure. Often the reason lies in trivial violations of operating conditions, which are easy to correct on your own.
Constant operation of the motor leads to overload of the unit components. At best, this threatens increased energy consumption. At worst, it’s a burnt-out compressor, the replacement of which is expensive. Therefore, it is important to quickly identify the source of the problem and eliminate it before the consequences become irreversible.
In this article we will look at the main reasons why The refrigerator does not turn offand consider ways to eliminate them. You will learn how to check the tightness of the seal, adjust the thermostat and diagnose a refrigerant leak without calling a technician.
Checking the operating mode and settings
Before looking for faults in the electrical circuit, it is worth eliminating the human factor. Often, users accidentally activate the "Super Freeze" (Super Freeze) mode. In this mode, the compressor works hard without turning off in order to freeze food as quickly as possible. On modern models Samsung or LG this mode can turn on automatically when the door is opened or power surges.
If you have loaded a lot of warm products, the appliance will work longer than usual. This is a normal reaction to heat stress. However, if after 12-18 hours the motor continues to hum without interruption, and a “coat” of ice has formed in the chamber, then the cooling cycle is broken. You need to check the temperature settings.
⚠️ Attention: If you have turned on the quick freeze mode, do not forget to turn it off after 24 hours. Prolonged operation in this mode may lead to overheating of the motor windings.
To check the current settings, refer to the instructions for your model. Typically the path looks like this: Menu → Settings → Operating modes. Make sure that the temperature sliders are set to the recommended values: from +2 to +5°C for the refrigerator compartment and -18°C for the freezer.
Chamber seal failure
One of the most common reasons, why compressor doesn’t turn off - it’s a loose door fit. If warm air from the room constantly enters the chamber, sensors record the increase in temperature and command the motor to operate continuously. Check if anything is preventing it from sealing tightly: hanging packaging, dishes on the shelf, or crumbs in the groove.
Pay special attention to the rubber seal. Over time, rubber dries out, cracks or becomes deformed. Dirt and grease adhering to the cuff will also compromise the seal. To check, use a simple test with a sheet of paper: clamp the sheet with a door around the perimeter. If it comes out easily and without resistance, then the seal is broken.
- 🧼 Wash the seal thoroughly with warm water and soap to remove greasy deposits.
- 🔥 If the rubber is deformed, try smoothing it with a hot hairdryer (be careful not to overheat).
- 🔧 Check the door hinges - they may be skewed and require adjustment.
In some cases, it is easier to replace the rubber seal than to try to restore it. The new cuff will ensure the necessary tightness, and the cycle will work.
☑️ Diagnosis of tightness
Problems with the thermostat and sensors
The thermostat (thermostat) is the “brain” that decides when to turn the refrigerator on and off. If it is faulty, the contacts may become stuck in the closed position. In this case, the compressor will work constantly, even if the deep-freezing temperature inside has already been reached. In mechanical models, the thermostat is located inside the chamber; in electronic models, an air sensor is used air sensor.
Signs of a malfunctioning thermostat are often accompanied by other symptoms. For example, food in the refrigerator compartment may freeze, turning into ice, or, conversely, the temperature will be higher than normal, but the motor will still not stop. Diagnostics requires disassembling the unit and “testing” the multim contacts
If you have a model with a system No Frost, several defrost sensors may be responsible for the temperature. The output of one of them may block the normal operating cycle.
How to check a thermostat with a multimeter?
To check, remove the thermostat and lower its sensitive tube into cold water with ice. Then call your contacts. If during cooling the contacts do not open (the sound does not disappear), the part is faulty and requires replacement.
Replacing a thermostat is a simple procedure, but requires care. It is important to install a new part with similar parameters, otherwise the operating modes will be disrupted.
Freon leakage and problems with the cooling system
If the refrigerator works without stopping, but there is no cold inside (or it is weak), there is a high probability of a refrigerant leak (freon). If there is not enough gas, the compressor tries to compensate for the lack of cold by running idle. This is the most dangerous mode for the motor, since cooling of the windings often occurs precisely due to circulating freon.
A leak can occur anywhere in the circuit: in the evaporator, condenser or places where tubes are soldered. Microcracks often form due to corrosion or mechanical damage during transportation. It is difficult to find a leak on your own, since freon is colorless and odorless.
| Symptom | Possible cause | Action |
|---|---|---|
| Motor is hot, no cold | Leak freon | Call a technician to find a leak |
| The refrigerator turns on for 1 minute, then pause | Clogged capillary tube | Purge of the system is required |
| There is a hum, but it is quieter than usual | Low pressure in the system | Checking the compressor and refueling |
To eliminate the leak, specialized equipment is required: a vacuum pump, a pressure gauge station and refueling scales. It is almost impossible to fix such a malfunction on your own.
Compressor malfunction
The most expensive breakdown is failure of the compressor itself compressor. If the motor hums but does not start, or starts for a few seconds and clicks (the thermal relay is triggered), this indicates an interturn short circuit or jamming of the piston group. In this case, the equipment may operate jerkily or continuously try to start.
Sometimes the reason lies not in the motor itself, but in the start-protection relay. This is a small box on the compressor housing. If it burns out, the motor will not receive the necessary impulse to start. Replacing the relay is inexpensive and is often done by hand.
⚠️ Attention: If the compressor gets very hot (more than 90°C) and has the smell of burnt wiring, further operation is prohibited. This can lead to a fire.
In modern inverter models, diagnostics are more difficult. There, an electronic control module is responsible for the operation of the motor. Failures in the board can simulate engine failure.
The influence of external factors and ventilation
A refrigerator, like any thermal one, needs to release heat to the environment. If the unit is installed close to a wall, in a niche without ventilation, or next to a radiator or stove, the heat transfer efficiency decreases. The compressor is forced to work longer to maintain the set temperature.
It is also important to consider the room temperature. If the room is hot (above +30°C), a standard refrigerator may not cope with the load and work almost without interruption. This is a physical feature of the Carnot cycle used in refrigeration machines.
- 🌬️ Provide a gap of at least 5-10 cm between the back of the refrigerator and the wall.
- 🧹 Regularly (once every six months) clean the condenser (grid at the back) from dust and animal hair.
- 🌡️ Do not install equipment in places exposed to direct sunlight.
Dust on the condenser acts as a heat insulator, interfering with cooling Freon. Cleaning with a vacuum cleaner or brush can reduce the condensation temperature and reduce the operating time of the compressor.
When you need to call a technician
Not all breakdowns can be repaired yourself. If checking the settings, seal and cleaning the condenser did not help, and the refrigerator continues to work without interruption, most likely the problem is within the system. Independent disassembly of units containing freon is prohibited and dangerous.
A technician is needed if:
- 🔨 A knocking or metallic clanging sound is heard when the compressor is operating.
- 🧊 Ice freezes in the freezer compartment, and ice freezes in the refrigerator compartment heat.
- ⚡ There are frequent power surges in the network, which could damage the electronics.
Professional diagnostics using a leak detector and pressure gauges will allow you to accurately determine the cause. In some cases, it is cheaper to buy a new refrigerator than to repair an old compressor.
Frequently asked questions (FAQ)
Why a new refrigerator does it work continuously on the first day?
When you turn it on for the first time, the empty chamber needs time to gain temperature. This may take from 2 to 24 hours depending on the model and volume. If the motor does not turn off after a day, check the settings.
Can the refrigerator not turn off due to a power surge?
Yes, a power surge could damage the thermostat or electronic control module. In this case, the “brain” of the refrigerator stops receiving correct temperature data and keeps the compressor on.
Is it dangerous if the refrigerator does not turn off at night?
This is dangerous primarily for the device itself. The risk of overheating and fire is minimal with proper wiring, but the life of the compressor in this mode is exhausted in a few days or weeks. It is also possible that food may defrost due to a violation of the defrost cycle.
How to understand that the thermostat has burned out?
If you unscrew the thermostat knob to the minimum position (maximum cold), and the compressor does not respond by changing the sound or frequency of switching on, or vice versa - it works constantly even at minimum, most likely the sensor is faulty.