After installing a new refrigerator or defrosting it owners are often faced with a situation where equipment works continuously without turning off for hours. This raises a natural concern: is the unit working properly or is it time to call a technician? The answer lies in the physical processes occurring inside the system and depends on many factors, including the room temperature and the initial state of the cameras.
The first start-up time can vary from 2 to 24 hours, and this is not always a sign of a breakdown. The compressor needs to develop a given temperature regime, cool the internal walls, shelves and loaded products. Understanding the principles of operation compressor-condensing unit will help to distinguish a normal situation from an emergency.
In this article we will analyze in detail the time intervals for various operating modes, the influence of the environment and technical nuances that determine the duration of the first cycle. You will also find out at what symptoms you should really sound the alarm and stop using the device.
Standard operating time at first start
Immediately after being plugged into the network, the refrigerator goes into the active phase of operation. The compressor engine starts and runs without interruption until the temperature sensors record that the set values have been reached. In normal mode, provided that the chambers are empty and the room is warm, this process usually takes from 2 to 4 hours.
However, if you have just defrosted the unit or brought it from the cold, the time may increase. The internal volume must cool evenly, which requires time for the refrigerant to circulate through the pipe system. Models with a system No Frost are characterized by a longer first cycle time due to the need to cool the evaporator and fan.
It is important to consider that modern inverter compressors operate on a different principle. They do not turn off completely, but reduce the speed, maintaining the temperature. Therefore, it may seem that the refrigerator is constantly humming, but this is a normal energy-saving mode, and not a sign of a malfunction.
If after 12-15 hours of continuous operation the motor does not turn off (or does not go into quiet mode), and the temperature inside the chambers remains high, this is a reason for diagnosis. The tightness of the circuit may have been broken or the thermostat has malfunctioned.
⚠️ Attention: If after 24 hours of operation the compressor does not turn off, but it is warm inside, immediately unplug the device. Long-term wear-and-tear operation can lead to burnout of the motor winding, which will require expensive replacement.
The influence of ambient temperature and load
One of the key factors affecting the duration of operation is the room temperature. If you install the refrigerator in the kitchen, where +25...+28°C, or, even worse, next to a stove or radiator, the system will have to work much longer. Thermal exchange is difficult, and condenser does not have time to give off heat.
Loading with products also plays an important role. Empty chambers cool faster than filled ones. If you have placed a large amount of warm food into the refrigerator that has just been turned on (for example, after defrosting the freezer or purchasing a large amount of food), the operating time will increase in proportion to the weight and initial temperature of the cargo.
There are certain climate classes of equipment that indicate the permissible operating temperature range:
- ❄️ N (Normal): from +16°C to +32°C (standard for most models).
- 🌡️ SN (Subnormal): from +10°C to +32°C (extended range).
- 🌴 T (Tropical): from +16°C to +43°C (for hot climates).
- 🌞 ST (Subtropical): from +18°C to +38°C.
Using equipment outside the recommended climate class may cause the refrigerator to operate almost non-stop. In winter, if the device is located on an unheated balcony, the oil in the compressor may thicken, which will also disrupt the operating cycle.
Differences for models with No Frost and drip system
The design of the cooling system directly affects the engine operation algorithm. In refrigerators with a drip system (Direct Cool), moisture freezes on the back wall and periodically thaws when the compressor rests. The cycles here are more pronounced: work - pause - work.
Units with No Frost equipped with fans and additional heating elements for defrosting the evaporator. After switching on, they require time not only to cool the air, but also to stabilize the operation of the defrost system. Often the first cycle of such models lasts longer - up to 6-8 hours before the automatic shutdown works.
Two-compressor models allow you to independently regulate the temperature in the refrigerator and freezer compartments. If you turn on such a refrigerator, one compressor may turn off earlier, reaching normal, while the second continues to work. This is absolutely normal and indicates that the separate control system is working properly.
It is important to understand the difference in noise. In models with No Frost you can hear not only the hum of the motor, but also the crackling of plastic, the noise of a fan or the gurgling of freon. These sounds can occur even when the compressor is formally “resting”, as the process of defrosting or refrigerant distribution is in progress.
Why are two-compressor models quieter?
Two-compressor systems often operate quieter, since each motor has less power and load compared to one powerful compressor, which must serve both chambers at once. In addition, they are less likely to turn on at the same time.
Technical reasons for long-term operation without shutdown
If the operating time exceeds reasonable limits (more than a day), it is worth considering technical faults. One of the common causes is a refrigerant (freon) leak. When there is a lack of gas in the system, the pressure drops, and the compressor tries to compensate for this by constantly working, but cannot reach the desired temperature.
Another common problem is a malfunction of the thermostat or temperature sensor. If the “brain” of the refrigerator does not receive the correct signal that the cold has already been collected, it will not give the command to stop the engine. In older models with mechanical control, this can be solved by replacing the thermostat.
It is also worth checking the rubber seals on the doors. If they are worn out, dirty or damaged, warm air from the room constantly enters the chamber. The compressor is forced to work continuously to compensate for the heat gain. You can check the tightness using a sheet of paper: clamp it with the door and try to pull it out - if it comes out easily, the seal requires replacement or adjustment.
Clogged capillary tube is another serious reason. Freon circulation is disrupted and the system cannot effectively cool the chambers. In this case, you can often hear a characteristic gurgling sound or, conversely, deathly silence when the motor is running (if the protection has tripped).
Comparative table of operating modes
For the convenience of assessing the condition of your device, we will provide data on how long the refrigerator should operate in various scenarios. These indicators are average and may differ depending on the model and manufacturer.
| Scenario | Expected operating time until the first stop | Is this normal? |
|---|---|---|
| First start (empty) | 2 - 4 hours | Yes, normal mode |
| After defrosting (with food) | 6 - 12 hours | Yes, cargo cooling is required |
| Hot room (+30°C and above) | Up to 18 hours (cyclically) | Yes, but not recommended |
| Continuous operation > 24 hours | More than a day | No, diagnostics required |
| Super Freeze mode | Up to 48 hours (manually) | Yes, if enabled by the user |
Pay attention to the “Super Freeze” mode. If you have activated this function with a button, the refrigerator will run non-stop until you turn it off or the timer expires (usually 24-48 hours). This is necessary for quickly freezing a large volume of food in order to preserve its structure.
⚠️ Attention: Do not leave the “Super Freeze” mode turned on on a permanent basis. This leads to rapid wear of the compressor and excessive power consumption.
Checklist: what to do when you turn it on for the first time
To minimize risks and ensure correct operation of the equipment, it is important to properly prepare it for startup. This is especially true for new devices that were transported in a horizontal position.
Following the sequence of actions will help avoid false alarms and extend the service life of the unit. Use this list to make sure you haven't missed anything.
☑️ Correct first launch
After the refrigerator has completed the first cycle and turns off (or switches to silent mode), you can gradually load food. You should not fill the chambers to capacity in the first hours - this will create an extra load on the system.
If you notice that after loading food the refrigerator stops turning off, try reducing the amount of warm goods or temporarily reducing the power (if there is an adjustment). Give the equipment time to adapt to the new thermal conditions.
When you need to call a technician
There are a number of signs that clearly indicate a breakdown, and waiting here makes no sense. If you experience these symptoms, attempting repairs on your own may only make the situation worse.
First, pay attention to the temperature. If the refrigerator hums for days, but it is warm inside (above +10°C in the refrigerator compartment), it means that the cooling capacity is impaired. Most likely, there is a freon leak or a clogged capillary.
Secondly, listen to the sounds. A metallic knock, loud clicks when starting, or a complete absence of sound when the power indicator is on indicate a problem with the start relay or the compressor itself. In such cases electric motor it may try to start, but it does not have enough power, which quickly leads to overheating.
Thirdly, visual inspection. If you see swelling in the back wall, rust in the compressor area, or traces of oil under the device, these are signs of system depressurization. Operating such a refrigerator is dangerous and ineffective.
Is it possible to turn on the refrigerator immediately after delivery?
It is strictly not recommended. If the refrigerator was transported in a horizontal position, the oil needs time (at least 2-4 hours, preferably 8-10) to drain back into the compressor crankcase. Switching on “dry” can lead to water hammer and jamming of the piston group.
Why does the refrigerator not turn off for a long time in winter?
If the refrigerator is in a cold room (below +10°C), the oil in the compressor becomes too thick, and the temperature sensor may not read the readings correctly. Many manufacturers do not recommend operating equipment at temperatures below the lower limit of the climate class.
Does the voltage in the network affect the operating time?
Yes, low voltage in the network (less than 190V) causes the engine to work with overload, hums louder and takes longer to reach temperature. In such cases, it is recommended to use a voltage stabilizer to protect the electronics and the compressor.
Is it normal for the sides of the refrigerator to be hot?
Absolutely normal. In modern models, the condenser (heat exchanger) is often built into the side walls. During the active phase of operation, they can heat up to 50-60°C. This indicates that the heat removal system is functioning correctly.
What to do if the refrigerator does not freeze after defrosting?
After defrosting, let it work for 3-4 hours without loading. If the temperature has not dropped during this time, check that the doors are tightly closed and that the fast freeze mode is not turned on (which sometimes blocks the sensors). If the problem persists, call a specialist.