The situation when the refrigerator works properly in the lower compartment, turning water into ice, but there is heat in the main chamber, is familiar to many owners of household appliances. This is a classic symptom of poor refrigerant circulation or a malfunction in the temperature control system. Often, users do not notice the problem right away: food in the refrigerator compartment begins to deteriorate, milk sours faster than usual, and condensation appears on the walls.
Modern models, be it Indesit, Atlant or Samsung, are designed on the principle that cold is generated in the freezer compartment and then distributed throughout the rest of the volume. If this process is disrupted, then the technically sound evaporator in the “freezer” continues to operate, while the main compartment remains without cooling. Understanding the physics of the process helps you quickly find the root of the problem without immediately resorting to calling a technician.
In most cases, the reason lies in one of several key systems: the compressor-condensing unit, the defrost system, or the elementary tightness of the circuit. Diagnostics it begins with an analysis of the accompanying symptoms: is the motor humming, is there ice on the back wall, is it working whether the fan. Ignoring the first signs can lead to complete breakdown of the unit and damage to a large stock of products.
Problems with the compressor and start relay
The heart of any refrigeration unit is the compressor. If the refrigerator freezes only in the freezer compartment, this often indicates that compressor works, but does not develop enough power to pump freon through the full cycle, or is turned on for a short time. In two-compressor models, the situation is simpler: one motor is responsible for the freezer, the second for the refrigeration compartment, and the failure of one of them localizes the problem.
In single-circuit systems, where there is only one motor, a partial loss of performance may be caused by the exhaustion of the piston group or valves. Freon circulates, the pressure is enough to create ice in a small volume of the freezer, but for a large volume of the refrigeration chamber it is no longer enough. It also often fails starting relay, which is responsible for starting the engine.
⚠️ Attention: If you hear a loud click when you try to start the engine, followed by silence or a buzzing sound that ends abruptly, this is a sure sign of a faulty starting relay or jamming compressor. Operation in this mode is dangerous due to overheating of the windings.
Checking the compressor requires caution. It is necessary to feel the motor housing: if it is hot to the point where it is impossible to touch it with your hand, it means that the unit is working with overload. A cold compressor while the refrigerator is running indicates that the electrical circuit is broken and the motor does not start at all, although the light in the chamber may be on.
Faults in the No Frost and defrosting
Owners of equipment with the system No Frost are characterized by the problem of the formation of a “snow coat” on the evaporator, which is hidden behind a plastic panel. If Defrost heating element, defrost thermostat or the timer fails, the ice does not melt, but grows. Over time, the ice cocoon blocks the channels through which cold air should enter the main chamber.
As a result, the fan circulates air inside the freezer, creating a low temperature there, but the flow does not enter the refrigerator compartment. You can visually notice this if you remove the back panel in the freezer: there will be a block of ice clogging the radiator. In such cases, it is necessary to completely defrost the unit during the day and replace the burnt-out elements of the defrost system.
- ❄️ Defrost heating element —a heating element that turns on periodically to melt the ice on the evaporator.
- 🌡️ Defrost thermostat —a sensor that turns off the heating element when a certain temperature is reached, so as not to overheat system.
- ⏱️ Timer or electronic module - a device that sets the intervals for turning on the defrost mode.
A common mistake is trying to chop off the ice with a knife. This can lead to damage to the evaporator tubes and leakage of freon. The correct one fault requires checking the heating element with a multimeter: if the resistance is infinitely high, the element has burned out and requires replacement. It is also worth checking the integrity of the wires going to the heater, as they often rot due to temperature changes.
☑️ Diagnostics of the No Frost system
Freon leakage and blockage of the capillary tube
One of The most insidious reason why the refrigerator is warm and the freezer is cold is a partial refrigerant leak or clogged capillary tube. Freon is a working fluid that, when evaporating, takes away heat. If its amount in the system decreases, the pressure drops. The refrigerant only manages to cool the first section of the circuit (the freezer), without reaching the main evaporator.
If there is a leak, you can often notice a swelling of the back wall inside the chamber or, conversely, a complete absence of frost on the evaporator. If something happens clogging (for example, moisture gets in and an ice plug forms, or the filter drier becomes clogged with oil breakdown products), circulation is also disrupted. The symptoms are similar: the freezer operates in high mode, but the refrigerator compartment does not cool.
| Symptom | Probable cause | Characteristic symptom |
|---|---|---|
| The motor runs constantly | Freon leakage | Warm side wall, no frost |
| The motor turns on rarely | Clogged system | Double sound of operation, pressure drops |
| Frost only at the inlet | Lack of refrigerant | Ice only at the beginning of the evaporator tube |
| Compressor is hot | Overload / Blockage | The unit is trying to push through the plug |
It is impossible to eliminate the leak or blockage on your own, as it requires evacuation of the system, replacement of the filter-drier and refilling with the exact amount of freon. Attempts to “add gas” without eliminating the cause will only lead to a temporary effect and eventual failure of the compressor due to wet operation.
Is it possible to determine a leak visually?
Often the location of the leak (especially in the foamed part of the housing) cannot be seen with the eye. However, if oily spots are visible on the floor under the refrigerator or at the joints of the tubes, this is a sure sign of depressurization, since freon circulates along with compressor oil.
Failure of the air damper
In modern models with a full system No Frost and one compressor for cold distribution answers special air damper. This is an adjustable damper that opens at the command of an electronic module, allowing cold air from the freezer to enter the refrigerator compartment. If the mechanism is stuck in the closed position or the drive motor is burned out, the cold simply does not reach the food.
You can check the operation of the damper by opening the door of the refrigerator compartment. Normally, you should hear the characteristic sound of the fan and feel the flow of cold air. If the damper does not open, the temperature in the chamber rises, although the freezer is working properly. Often the problem is solved by cleaning the mechanism or replacing the servo drive.
Sometimes the damper becomes overgrown with ice and cannot close or open completely. In this case, defrosting is required. It is also worth checking the temperature sensor in the refrigerator compartment: if it shows incorrect data, the control module may simply not give a command to open the damper, “thinking” that there is already cold inside.
The influence of seals and chamber tightness
It would seem that if the freezer freezes, then the tightness has nothing to do with it. However, if sealing rubber the refrigerator door is damaged, dirty, or simply does not fit tightly, warm, moist air from the room is constantly entering the chamber. The cooling system simply does not have time to compensate for this heat influx, especially if the door is often opened.
As a result, a layer of snow (in drip systems) or an ice crust forms on the back wall, which blocks the access of cold. Visually it looks like this: the refrigerator seems to be humming, but inside it’s +10...+15 degrees. You can check the seal with a simple test with a sheet of paper: press the sheet between the door and the body around the perimeter. If it is pulled out without effort, the tightness is broken.
- 🧼 Contamination - fat and sticky dirt do not allow the rubber to adhere tightly to the metal.
- 📉 Deformation - the rubber could “remember” the position or stretch over time.
- 🧊 Ice - freezing of the seal to the body due to moisture.
To restore tightness, sometimes it is enough to wash the rubber with warm water and soap and lubricate it with silicone grease. If the seal is deformed, you can try straightening it with a hairdryer (carefully, without overheating) or replace it with a new one. Ignoring this problem causes the compressor to work hard, trying to cool the “street.”
⚠️ Attention: Do not use aggressive chemicals or abrasives to wash the seals. This destroys the structure of the rubber, making it hard and brittle, which will finally break the seal.
Electronic control module and sensors
In smart refrigerators it monitors everything electronic module. It reads readings from temperature sensors in both chambers and controls the compressor, fan and heating elements. If the sensor in the refrigerator compartment “fails” (shows that it is -5°C, although in fact it is +15°C), the module will not turn on the cooling for this compartment, considering the temperature to be normal.
Often the problem lies in oxidation of contacts or broken wires going to the sensors. In such cases, error codes may appear on the display (if there is one). Deciphering the code allows you to accurately determine which node requires attention. Replacing the sensor yourself is a simple procedure, but requires precise selection of an analogue in terms of resistance.
Failures in the control module firmware can also lead to incorrect operation. In rare cases, a full reset (hard reset) helps by unplugging the device from the network for 15-20 minutes. If, after switching on, the operating logic has not been restored, there is likely a malfunction of the control board itself, requiring re-soldering of elements or replacement.
Frequently asked questions and answers (FAQ)
Why did the refrigerator work after defrosting, but a week later it stopped freezing again in the main chamber?
This is a classic sign of a malfunction of the defrosting system (No Frost). During defrosting, you removed the ice plug and the air started flowing again. But since the heating element, timer or thermostat is faulty, ice has accumulated again and blocked the channels. A burnt-out element of the defrost system needs to be replaced.
Is it possible to operate a refrigerator if it freezes only the freezer?
For a short time - yes, if you need to store frozen food. However, continuous operation in this mode is harmful to the compressor, which may run non-stop, trying to gain temperature. In addition, the food in the refrigerator compartment will quickly spoil.
How long does it take to defrost the refrigerator to check?
It takes at least 24 hours for the ice in the hidden evaporator channels and air ducts to completely melt. Defrosting for 2-3 hours is often insufficient, since the ice remains in the depths of the channels, and the problem does not disappear.
Why is the back wall of the refrigerator covered with snow, but it is warm inside?
Snow on the back wall is an indicator that moisture from the air condenses and freezes, but the cold is not distributed throughout the volume. This may be a sign of a loose door fit, a fan malfunction, or problems with freon circulation.