The situation when the refrigerator continues to hum, the light inside is on, and food begins to rapidly deteriorate is familiar to many owners of household appliances. This state of panic is understandable, because a violation of the temperature regime threatens the loss of supplies and the need for expensive repairs. However, before calling a technician or running to the store for a new unit, it is worth conducting an initial diagnosis. Often the reason lies in banal things that can be fixed on your own in a matter of minutes.
Modern compressor refrigerators are complex systems where even a minor malfunction in the operation of one element can disrupt the entire cooling cycle. It is important to understand the difference between when the equipment simply does not turn on, and when the engine is running, but there is no cold. In the second case, the compressor may hum constantly or, conversely, be silent, although the indicators are on. The most common reason for the lack of cold when the engine is running is a refrigerant leak or malfunction thermostat. Understanding the principles of operation will help you quickly determine the search vector for the problem.
In this article we will look at the main reasons why the refrigerator has stopped freezing, but is still working. We will consider both external factors, such as improper installation or overload, and internal breakdowns that require specialist intervention. You will learn how to check the seals, defrost the No Frost system and understand when it’s time to sound the alarm.
Primary diagnostics: external factors and settings
Before looking for complex technical faults, it is necessary to eliminate basic operating errors. Often, users themselves, without noticing it, violate the operating conditions of the equipment. For example, the refrigerator may be overloaded with food, blocking the circulation of cold air. It is also worth checking whether the door is pressed by a foreign object or kitchen furniture.
Pay attention to the position of the temperature regulator. If the house is hot and you have set the cooling mode to minimum, the equipment may not be able to cope with the load. In models with electronic control, a failure could occur due to a power surge. Try to perform full reset or simply reboot the device by unplugging it for 15-20 minutes.
Check the tightness of the door. The rubber seal wears out over time, cracks, or gets dirty, allowing warm air to get inside. The compressor is working hard, trying to compensate for heat loss, but the temperature does not drop. Wipe the seal with a soft cloth and check if there are any creases on it.
If you notice that the problem appeared after general cleaning or rearrangement, make sure that the gap between the back wall of the refrigerator and the wall is at least 5-7 cm. Impaired condenser ventilation leads to overheating and stops the cooling process.
Problems with the defrosting system in No Frost models
Refrigerators with the No Frost system (or Low Frost) do not require manual defrosting, but this comes at the cost of design complexity. They are equipped with special heaters, timers and sensors that periodically turn off the compressor and turn on the heating element to defrost the evaporator. If one of these elements fails, a coat of ice builds up on the evaporator, blocking air circulation.
As a result, the chamber may be light and even a little cool near the floor, but the products on the upper shelves are warmer. A characteristic sign of such a malfunction is that the compressor runs longer than usual or, conversely, almost does not turn on, since the sensor does not give the command to start. Ice blocks the channels through which cold air should enter the chamber.
- ❄️ Faulty heating element: The heating element burns out and stops melting the ice, which is why the evaporator becomes overgrown with a “fur coat.”
- ⏱️ Defective defrost timer: The mechanism “sticks” in cooling mode and never switches system into defrost mode.
- 🌡️ Defective defrost sensor: The sensor incorrectly reads the evaporator temperature and does not send a signal to turn on the heater.
To diagnose the No Frost system, partial disassembly of the rear wall is often required freezer. Visually, you can see ice build-up on the evaporator if you remove the panel. However, to accurately determine the malfunction (the heating element or sensor has burned out), you will need a multimeter to “test” the circuit.
It is important to note that after repairing the defrosting system, it is necessary to thoroughly dry all elements before turning on the equipment. Remaining moisture can freeze again and block the fan.
Refrigerant leak: signs and consequences
Refrigerant (freon) is the “blood” of the refrigerator, circulating in a closed circuit and providing cooling. If the refrigerator has stopped freezing, but the compressor runs continuously and gets very hot, there is a high probability of a leak. Freon can escape through microcracks in the tubes formed due to corrosion or mechanical damage.
Unlike older models, modern refrigerators are often filled with environmentally friendly gases that are less noticeable when leaking. Therefore, you may not feel the smell. The main symptom is the absence of cold when the engine is actively running. In some cases, you may notice swelling or traces of oil on the condenser tubes (grid at the back).
⚠️ Attention: Refilling the refrigerator with freon yourself is impossible without special equipment and a license. An attempt to add gas “by eye” will lead to compressor failure.
The process of restoring the tightness includes finding the leak, sealing the hole and evacuating the system before refilling. This is a complex procedure that requires skills and tools. If you hear hissing or notice oily spots inside the chamber or at the back of the unit, immediately unplug the device.
Compressor and starting faults relay
The compressor is the heart of the refrigeration unit. If it is faulty, the refrigerant cannot circulate. However, often the problem lies not in the motor itself, but in the start-up relay. This device is responsible for starting the engine and protecting it from overloads. If the relay is burned out, the compressor may hum, click, but not start, or it may start for a couple of seconds and stall.
In the case when the motor runs but does not create the necessary pressure in the system, we may be talking about an interturn short circuit of the windings or mechanical wear of the piston group. In such situations, the refrigerator may cool slightly but not reach the set temperatures. Replacing a compressor is an expensive repair, which is often comparable to the cost of used equipment.
You can check the start relay visually and by ear. If you hear a loud click when you turn it on, followed by a buzzing sound and a second click (safety shutdown), most likely the problem is with this component. Replacing it is inexpensive and is often done by craftsmen at home.
| Symptom | Probable cause | Difficulty of repair |
|---|---|---|
| Buzzes, but does not start | Start relay or wedge compressor | Medium |
| Works constantly, does not freeze | Freon leak or clogged capillary | High |
| On for 10 seconds and off | Malfunction of the starting relay | Low |
| The back wall gets very hot | Condenser contamination or leakage | Medium |
If you If you decide to replace the relay yourself, be sure to purchase a part with exactly the same marking data. There are no universal solutions here, and installing an unsuitable relay can lead to burnout of the compressor windings.
Clogged capillary tube
The capillary tube is the thinnest channel connecting the condenser and the evaporator. It is here that a sharp drop in refrigerant pressure occurs, which causes its evaporation and cooling. Over time, oil oxidation products or moisture may accumulate in the system, which turns into an ice or solid plug.
When clogged, the compressor works with increased load, trying to push freon through the obstacle. In this case, the condenser (grid at the back) may heat up unevenly: only the area up to the blockage remains hot, and the rest remains cold. This is one of the key diagnostic signs.
Removing the blockage requires professional cleaning of the system with high pressure nitrogen or replacement of the capillary tube. It is impossible to perform this procedure at home. Attempts to “break through” the blockage with pressure changes without evacuation will lead to moisture entering the system, which will cause corrosion from the inside.
Why does blockage occur?
The main reason for capillary blockage is moisture entering the system due to poor-quality filling or a violation of the tightness. Water freezes in a narrow channel and blocks the freon flow. The second reason is the oxidation of the oil, which turns into slag when the compressor overheats.
Failures in the operation of the electronics and thermostat
In modern models, an electronic control module monitors everything. If it receives incorrect data from sensors or does not work correctly, the refrigerator stops freezing. The thermostat (or temperature sensor) can “lie”, telling the control unit that it is already cold in the chamber, although in fact it is warm there. As a result, the compressor simply does not receive the command to turn on.
You can check the mechanical thermostat by closing its contacts. If the refrigerator starts working after this, it means the regulator is faulty. In electronic systems, diagnostics are more complicated and require checking the resistance of the sensors. It is also worth inspecting the control board for burnt elements or swollen capacitors.
Sometimes the problem lies in the wiring. Frayed wires, oxidized contacts in connectors - all this can interrupt the power supply circuit of a compressor or fan. A careful visual inspection of the internal wiring harnesses often helps to find a break.
☑️ Diagnostics before calling a technician
Do not ignore the flashing indicators on the control panel. Many manufacturers provide error codes that indicate a specific malfunction by flashing lights. Decoding the codes for your model Bosch, LG, Indesit or another brand can be found in the instructions or on specialized forums.
When you need to call a specialist
Independent repair is justified only in cases of simple malfunctions: replacing a light bulb, seal, start relay or defrosting the No Frost system. If the problem is related to a sealed circuit (freon, capillary) or requires disassembling the compressor, it is better to trust the professionals.
A master is needed if:
- 🛠️ Welding of pipes and vacuuming of the system is required.
- 🔋 There is a suspicion of a burnt compressor.
- 💧 Traces of oil were found inside the chamber.
- ❄️ After complete defrosting (24 hours), the refrigerator did not begin to freeze.
Contacting the service center guarantees the use of original spare parts and a guarantee for the work performed. This is especially important for expensive equipment, where the cost of an error during self-repair can be fatal.
⚠️ Attention: If your refrigerator is under warranty, any independent repair (even replacing a light bulb with a broken seal) will lead to loss of the manufacturer's warranty.
Remember that timely contact with a specialist can save compressor from burnout. Operation of equipment in abnormal mode (for example, during a freon leak) quickly destroys the most expensive component of the unit.
Prevention and proper care
To avoid situations when the refrigerator stops freezing, it is important to follow the operating rules. Regularly, at least once a year, clean the condenser (grid at the back) of dust and animal hair. A heat exchanger clogged with dust leads to overheating of the compressor and increased pressure in the system.
Do not place hot foods in the chamber and do not load the refrigerator to capacity with food, blocking the air ducts. Monitor the condition of the seals: wash them and check the tightness of the seal. If the door does not close tightly, the compressor will wear out.
Following these simple rules will extend the life of your refrigerator and keep food fresh for many years. Regular maintenance is cheaper and easier than major repairs or buying new equipment.
Why does a refrigerator freeze only in the freezer?
Most often this indicates a freon leak (the residual amount cools only the small circuit of the freezer) or a malfunction of the damper that blocks the cold supply channel to the main chamber. It is also possible that the channel in the No Frost system may freeze over.
Is it possible to use a refrigerator if it does not freeze?
You cannot use it to store food - it will spoil. It is also not recommended to leave it on, especially if the cause is a leak or a malfunction of the compressor, as this can lead to final failure of the equipment or a fire.
How long should defrosting last?
It takes from 12 to 24 hours for the ice to completely thaw and moisture to evaporate from hard-to-reach places (especially in the No Frost system). Forcibly accelerating the process with a hair dryer can damage plastic parts and seals.
What to do if, after defrosting, the refrigerator still does not freeze?
If after 24 hours of defrosting and turning on the network for 2-3 hours, the temperature does not drop, then the problem is technical (leakage, breakdown of the compressor, electronics). It is necessary to call a specialist for diagnostics.