The situation when the upper chamber of the refrigerator stops cooling food, while the freezer continues to freeze properly, is one of the most common complaints from home appliance owners. This phenomenon often causes bewilderment, since it seems that if one unit functions, then the entire mechanism must work equally efficiently. However, the design of modern cooling systems is such that a failure in one unit can locally disrupt the circulation of the refrigerant without stopping the operation of the compressor completely.
Before calling a technician or disassembling the unit, it is necessary to carry out initial diagnostics. Temperature violation in the main chamber it can be caused by both trivial reasons such as a loosely closed door, and serious technical problems such as freon leakage or clogged capillary tube. Understanding the operating principle of No Frost system or drip defrosting will help you quickly localize the problem.
In this article we will analyze in detail the mechanics of the process, explain why the compressor is humming, but there is no cold, and describe the algorithm actions to independently identify the breakdown. It is important not to ignore the first signs of a malfunction, as this can lead to damage to a large number of products and expensive repairs.
Principle of operation and distribution of cold in the chamber
To understand the nature of the malfunction, you need to understand the basic flow pattern of the refrigerant. In most modern models, freon first enters the evaporator of the freezer, where it actively boils and heat is removed. This is why the freezer often “works” even when the main chamber is already warm.
After the freezer, the refrigerant must pass through capillary tube and enter the evaporator of the refrigeration compartment. If an obstacle occurs along this path or the pressure in the system drops, circulation is disrupted. As a result, the evaporator in the upper compartment remains warm, despite the fact that the compressor continues to operate normally.
In systems with one compressor and one cooling circuit, the air is distributed by force or natural convection. If the fan stops or the damper jams in the closed position, cold air simply does not enter the main compartment.
It is important to consider that in models with Full No Frost a complex system of dampers and sensors is responsible for the distribution of flows. A failure in the electronics can give a command to close the damper, even if the compressor is physically working.
Refrigerant leak: the most common cause
If you hear that the compressor is running continuously without turning off, but the temperature in the main chamber does not drop below +10...+15°C, it is highly likely that it has occurred freon leak. There is not enough gas left in the system to create the pressure necessary to pass the refrigerant through the entire circuit, so there is only enough gas for the first section - the freezer.
Leaks often occur in places where pipes are soldered or due to corrosion of the evaporator, especially if you used sharp objects to defrost ice. Even a microscopic hole leads to the gradual disappearance of gas from the system. This can be visually noticed by swelling of the back wall of the refrigerator or the appearance of yellowish rust spots.
It is impossible to fix this problem on your own, as it is required:
- 🛠️ Finding the leak using a leak detector or soap solution.
- 🔥 Sealing damage and replacement of the damaged section of the tube.
- 💨 Evacuation of the system and filling with new freon under precise pressure.
Attempts to simply “add gas” without eliminating the cause of the leak will only give a short-term effect, after which the situation will repeat.
Clogged capillary tube or filter-drier
Another common reason why the refrigerator does not coolis blockage of a narrow section of the line. The freon circulation system has a filter drier that traps moisture and debris. Over time, it can become clogged with oil breakdown products or oxidation, which creates a blockage.
When clogged, the compressor tries to push freon, hums and heats up, but there is no circulation. A characteristic sign is that the condenser grid at the back of the refrigerator remains cold or warm only at the very beginning, and does not warm up over the entire area, as it should be during normal operation.
Sometimes the blockage is temporary. When the appliance is disconnected from the network for 10-12 hours, the ice plug in the capillary may melt and the refrigerator will start working again. However, this is a temporary phenomenon, and the cycle will soon repeat.
Why can’t you ignore the blockage?
Prolonged operation of the compressor with a clogged system leads to its overheating and eventual burning of the windings, which significantly increases the cost of repairs.
To eliminate the malfunction, the technician will need:
- ❄️ Purge the system with nitrogen under high pressure.
- 🔁 Replace the filter drier with a new one.
- 🔄 Evacuate and charge with refrigerant.
Compressor malfunction: loss of performance
The compressor is the “heart” of the refrigerator. It happens that the motor hums, vibrates and turns on on a timer, but does not create enough freon to pump the freon. This condition is called "loss of productivity." Most often, this occurs due to wear of the valves inside the compressor. pressure for pumping freon. This condition is called "loss of productivity." Most often this occurs due to wear and tear on the valves inside the compressor.
In this state, the compressor can only create pressure on a small circuit (freezer), but there is no longer enough strength to push the gas through the full cycle. Diagnosing this problem at home is difficult, since it requires connecting a manometric manifold to measure suction and discharge pressure.
If the diagnosis of “weak compressor” is confirmed, there is only one way out - replacing the unit. Repairing an old motor by replacing valves is not economically feasible and provides extremely low reliability.
Problems with the defrosting system (for No Frost)
In refrigerator systems No Frost situation when the freezer works, but the refrigerator compartment is warm, often associated with freezing of the evaporator. If the defrosting heating element, thermostat or timer fails, the ice does not melt, but grows in layers.Eventually, a block of ice blocks the ventilation ducts and cold air stops flowing into the main chamber.
Symptoms of this malfunction:
- 🧊 A thick layer of ice or ice is visible on the back wall of the freezer frost.
- 🔇 The fan may hum or not make noise at all, since ice interferes with its blades.
- 🌡️ The temperature in the refrigerator compartment rises to room temperature.
In this case, complete defrosting of the refrigerator is required (at least 24 hours with open doors) and subsequent replacement of faulty elements of the defrost system.
☑️ Diagnostics of the No Frost system
Failure of the damper or thermostat
In some models, especially two-compressor or with a multi-flow system, a special one is responsible for the supply of cold air damper. It is controlled electronically and opens only when the sensor detects an increase in temperature in the chamber.
If the damper is stuck in the closed position or the drive motor is burned out, the cold simply does not enter the compartment. Also, the cause may be a faulty thermostat (or temperature sensor), which “thinks” that it is already cold in the chamber and does not give the command to cool.
Diagnostics of these components requires disassembling the internal panel of the refrigerator. It is necessary to check the integrity of the wiring going to the damper and make sure that the mechanism moves freely.
Comparative table of symptoms and causes
For ease of diagnosis, we will summarize the main symptoms in a single table. This will help you quickly navigate the nature of the breakdown.
| Symptom | Probable cause | Nature of compressor operation | Difficulty of repair |
|---|---|---|---|
| Freezer freezing, top is warm | Freon leak | Works without stopping | High (needs a technician) |
| Ice on the back wall of the freezer | System malfunction defrost | Operates in normal mode | Average (replacement of heating element/sensor) |
| Heat everywhere, but the freezer can barely hold | Clogged capillary tube | Humming, heating up, may click | High (blow-out, refueling) |
| Cold, but the compressor does not turn off | Loss of compressor performance | Working continuously | High (motor replacement) |
| It’s warm in the chamber, normal in the freezer | The damper or fan is jammed | Can work cyclically | Average (mechanical/electrical) |
Analysis of the table shows that external manifestations are often similar, but the reasons are radically different. An accurate diagnosis can only be made by a specialist with the equipment.
⚠️ Attention: If you notice that the compressor is running “pull” (it barely starts and immediately stalls with a click), immediately unplug the refrigerator. Further attempts to turn on may permanently burn out the starting relay or motor windings.
Frequently asked questions (FAQ)
Can I continue to use the refrigerator if it does not freeze in the main chamber?
Short-term use is possible for storing products that do not require extreme cold, but you cannot leave the equipment in this condition for a long time. Operating the compressor without shutting it off leads to its overheating and failure, which will significantly increase the cost of repairs.
Why did the refrigerator start working normally after defrosting, but after a week it stopped working again?
This is a classic sign of a clogged capillary tube or the initial stage of a freon leak. Water that entered the system during defrosting temporarily removed the ice blockage, but the cause (moisture or debris in the system) did not go away. Professional blowing and filter replacement are required.
How much does it cost to repair if the refrigerator stops freezing?
The cost depends on the breakdown. Refilling with freon and finding the leak is usually cheaper than replacing the compressor. The exact price can only be given after diagnosis by a technician on site, since the price consists of the cost of spare parts and the complexity of the work.
Is it possible to replace the thermostat yourself if the refrigerator does not turn off?
Theoretically, this is possible if you have skills in working with electricians and tools. However, access to the thermostat often requires partial disassembly of the housing. If you are not confident in your abilities, it is better to entrust this to professionals so as not to break the seal of the chambers.
⚠️ Attention: Do not try to solder refrigerator tubes yourself without special equipment and skills. Using the wrong solder or violating the soldering technology will lead to repeated leakage and damage to the compressor by combustion products.