The situation when the temperature in the refrigerator suddenly rises and food begins to spoil is familiar to many owners of household appliances. Most often, users notice that top of the refrigerator stops cooling, while the freezer continues to operate normally or, conversely, functions intermittently. This is an alarm signal indicating a problem in the circulation of the refrigerant or a malfunction in the temperature control system.
Ignoring the problem at an early stage can lead to a complete stop of the compressor or spoilage of a large volume of food. It is important to understand that modern models, be it Indesit, Atlant or Liebherr, have similar principles of operation of the No Frost or static cooling system. However, the reasons for the breakdown may differ radically depending on the design of the device and the age of the equipment.
In this article we will analyze in detail the main mechanical and electrical faults that lead to a lack of cold in the upper compartment. We will look at the symptoms that will help you carry out initial diagnostics yourself, and determine when you need to call a technician and when you can try to fix the problem on your own.
Symptoms and initial diagnosis of the malfunction
Before you begin disassembling the unit, you need to accurately determine the nature of the malfunction. Users often confuse the lack of cold with an incorrect thermostat setting. If upper chamber it is not freezing, but it is light inside and the compressor is running non-stop, this may indicate a refrigerant leak. In systems with one compressor, freon first passes through the freezer, and only the remaining cold enters the refrigerator compartment.
Pay attention to the operation of the compressor. If it turns on for a few seconds, makes a clicking noise, and turns off, that's a sign of an overload or a problem with the start relay. In cases where the motor hums constantly, but there is no cold, most likely the capillary tube has become clogged. Also an important indicator is the presence of frost: if the evaporator in the freezer is covered with an uneven layer of ice or a “cap” only at the entrance of the tube, this confirms a circulation violation. freon leak or clogged capillary tube. The presence of frost is also an important indicator: if the evaporator in the freezer is covered with an uneven layer of ice or a “cap” only at the entrance of the tube, this confirms a circulation problem.
⚠️ Attention: If you hear a hissing sound when the refrigerator is operating or smell a specific smell, immediately unplug the appliance. and ensure the room is ventilated. This may indicate a leak of flammable refrigerant (isobutane), which creates a risk of fire.
To accurately make a “diagnosis,” it is useful to know the model of your device. Different manufacturers use different cooling schemes. For example, in two-compressor models Bosch or Siemens the lack of cold in the upper compartment when the freezer is running most often indicates a breakdown of the refrigerator's own compressor or a leak in this particular circuit.
Refrigerant leakage as the main reason
The most common reason why the top of the refrigerator does not freezeis a banal freon leak. The refrigerant circulates in a closed circuit, and if a microcrack forms in the system, the gas gradually evaporates. Since in most single-compressor refrigerators freon first enters the freezer, if there is a shortage of it, there is only enough cold for the freezer evaporator, and it simply does not reach the upper compartment.
Leaks often occur in places where pipes are soldered or in foamed parts of the body, where the metal is subject to corrosion. It is difficult to visually detect such a problem, since the tubes are hidden by thermal insulation. An indirect sign may be swelling of the side walls of the case or the appearance of rust spots at the joints. If the compressor runs non-stop, trying to gain temperature, but thermostat does not turn it off, this is a sure sign of loss of system tightness.
The process of restoring tightness requires professional equipment. The technician must locate the leak using a leak detector, repair the damage, and refill the system with refrigerant. It is impossible to perform this operation independently without a vacuum pump and a pressure gauge station.
- 🔍 Visual inspection: Check the back wall and the entry points of the tubes into the housing for oily stains (oil often comes out along with freon).
- 🌡️ Analysis of work: If the freezer is freezing and the temperature in the refrigerator compartment is higher +10°C, the probability of leakage is more than 80%.
- 🛠️ Difficulty of repair: You need to call a specialist with equipment for refueling and searching for leaks.
Malfunctions of the defrost system (No Frost)
In refrigerators with the system No Frost the lack of cold in the upper chamber is often associated with a violation of the defrost cycle evaporator. If the defrost heating element, defrost thermostat or timer (or electronic control module) fails, a “coat of ice” begins to build up on the evaporator. Over time, this ice completely blocks the channels through which cold air should enter the refrigerator compartment.
As a result, the fan moves the air, but it cannot pass through the ice jam. The freezer can continue to freeze, since the evaporator is located there, but the cold is not distributed throughout the entire volume. A characteristic sign of such a malfunction is that after the refrigerator is completely defrosted (for 24 hours with the doors open), it begins to work normally, but after 1-2 weeks the problem returns.
For diagnostics, you need to remove the back panel in the freezer and inspect the evaporator. If it is covered with ice, check the defrost circuit. It often burns out itself Defrosting heating element or the sensor that should give the command to turn on the heating fails. In models Samsung and LG there is also often a break in the wires going to the heater due to constant heating and cooling cycles.
⚠️ Attention: When checking the defrosting heating element, be sure to disconnect the refrigerator from electrical networks. Using a multimeter with the device turned on can lead to a short circuit and electric shock.
How to check a defrost heating element with a multimeter?
Switch the multimeter to resistance measurement mode (Ohms). Disconnect the wires from the heating element. Touch the probes to the heater contacts. If the device shows a resistance within 200-400 Ohms, the heating element is working. If the screen shows “1” or “OL” (break), the heater is burnt out and requires replacement.
Clogged capillary tube
Another technical reason why top of the refrigerator loses cold is a clogged capillary tube. During operation, microscopic oxide particles may form in the cooling system, oil may become waxed, or technological contaminants may remain. These substances collect in the narrowest point of the system - the capillary tube, blocking the freon flow.
Symptoms of a blockage are very similar to a leak: the compressor works constantly, the freezer can freeze weakly or only at the entrance of the tube, and it is warm in the refrigerator compartment. You can distinguish a clog from a leak by the temperature of the condenser (the grille at the back or the side walls). When there is a leak, the condenser is cold or slightly warm, and when clogged, it can be hot at the beginning and cold after the blockage, often accompanied by a characteristic gurgling sound.
Removing the blockage is a complex procedure that requires purging the system with high pressure nitrogen and replacing the filter drier. It is almost impossible to carry out high-quality repairs at home. Partial help may consist of trying to “stir up” the system with a long period of inactivity (up to 2-3 days), but this gives only a temporary effect.
| Symptom | Freon leak | Capillary clogged | Malfunction Heating element |
|---|---|---|---|
| Compressor operation | Constant, non-stop | Constant, may overheat | Cyclic (on/off) |
| Temperature rear | Cold grill | Hot at the beginning, cold further | Normal |
| Defrost effect | Does not help | Short-term improvement | Works for 1-2 weeks |
| Sounds | Silence or hum | Gurgling, hissing | Normal |
Problems with the fan and air distribution
In modern models with a system No Frost a special fan is responsible for circulating cold air. If the top of the refrigerator does not freezethere is ice in the freezer, the fan may have stopped or its duct has frozen. The fan may jam due to ice getting on the blades or its electric motor may fail.
It is also worth checking the damper that regulates the air flow (if it is provided for in the design). In some models Electrolux i Zanussi the damper is controlled by a solenoid and may get stuck in the closed position, preventing cold from entering the upper chamber. You can check the operation of the fan by opening the freezer door (on many models, when the door is open, it turns off, so you need to find and press the door open sensor).
If the fan does not spin, but voltage is supplied to it, it must be replaced. If it hums but stays still, the axle may be frozen. In this case, defrosting often helps, but it is better to check the condition of the door seals, since the entry of moist air causes excessive icing.
- ❄️ Icing: Ice on the fan blades blocks its rotation, requiring complete defrosting.
- 🔊 Noise: Humming without rotation indicates jamming fan motor.
- 🔄 Circulation: Without a working fan, cold heavy air remains below, in the freezer.
☑️ Fan diagnostics
Failures in the electronic control module
In electronically controlled refrigerators (where the temperature is set in degrees on the display), the reason for the lack of cold may be a malfunction control module. The board could freeze, experience a power surge, or one of its elements responsible for switching the compressor or fan could fail.
A simple system reboot often helps. To do this, you need to unplug the refrigerator for 10-15 minutes and then turn it on again. If after this procedure the device begins to work correctly, it means that a software failure has occurred. If the problem recurs, the board needs to be diagnosed by a technician.
It is also worth checking the temperature sensors (thermistors). If the sensor in the refrigerator compartment shows incorrect data (for example, that it is -20°C, when in fact it is +20°C), the control module simply will not give the command to cool. Replacing the sensor usually solves the problem.
⚠️ Attention: Electronic modules are sensitive to voltage changes. If your network frequently fluctuates electricity, it is recommended to use a voltage stabilizer to prevent expensive repairs to the control board.
Frequently asked questions and answers (FAQ)
Why did the refrigerator start to freeze after defrosting, and then stopped again a week later?
This is a classic sign of a malfunction of the defrost system in No Frost refrigerators. Most likely, the defrost heating element, defrost sensor or timer has burned out. Ice builds up on the evaporator, blocking air flow. The faulty defrost circuit element needs to be replaced.
Is it possible to operate the refrigerator if the upper chamber does not freeze?
For a short time - yes, if the compressor does not overheat. However, prolonged operation in this mode (especially if there is a freon leak or a blockage) leads to the compressor operating without stopping, which drastically reduces its service life and can lead to engine burnout. Food in the upper compartment will quickly spoil.
How much does it cost to repair if the top of the refrigerator stops freezing?
The cost depends on the reason. Replacing the heating element or sensor will cost the least. Freon refilling and leak detection are more expensive. The most expensive repair is replacing the compressor or electronic module. Only a technician can tell you the exact amount after on-site diagnostics.
Why in a two-compressor refrigerator the top does not work, but the bottom freezes?
In such models, each chamber is responsible for its own cooling circuit. If the top does not freeze, then the problem is in the refrigeration chamber circuit: a freon leak in this particular circuit, a malfunction of the second compressor, or a clogged capillary in the upper compartment.