The situation when you open the refrigerator door in the hope of getting food, and heat blows from there, while the freezer continues to freeze properly, causes bewilderment and panic. This is a classic symptom that indicates that the cooling system has ceased to perform its full function. Most often, the problem lies in a disruption in the circulation of the refrigerant or malfunction of the automation, and not in a complete breakdown of the unit.
In modern models, especially those equipped with a system No Frost, air circulates along a single circuit, and the breakdown of one element can unbalance the temperature conditions in different compartments. It is important not to ignore the first signs: if food begins to deteriorate and condensation appears on the walls, it is necessary to immediately carry out diagnostics. In this article, we will analyze the main technical reasons why refrigerator stopped cooling, and we will determine what steps you can take on your own.
Before calling a technician, it is worth conducting an initial visual inspection and eliminating common operating errors. Sometimes the reason lies in the fact that the door was not closed tightly or there was a power surge that threw off the thermostat settings. However, if the problem persists for more than a day, there is a serious problem that requires intervention.
Understanding how your model works is the key to quick diagnosis. In two-compressor systems, the breakdown of one unit does not affect the operation of the other, while in single-compressor units with one compressor failure of the defrost system or clogged capillary will lead to heat in the main chamber when the freezer is running.
⚠️ Attention: If you hear a loud click followed by silence and the refrigerator stops making its normal operating sounds, do not try to turn it back on immediately. Allow the motor to cool for 2-3 hours to avoid a wedge of the piston group.
Problems with the defrost system in No Frost refrigerators
The most common reason why it is warm in the main chamber and cold in the freezer is a malfunction of the system automatic defrosting. In models No Frost the evaporator is located in a hidden compartment, and frost constantly forms on it, which must periodically melt. If this process is disrupted, the “coat” of ice grows and blocks the ventilation ducts.
As a result, cold air simply cannot enter the refrigerator compartment, remaining locked in the freezer compartment or around the evaporator. Visually, you may not notice ice, since it is hidden by plastic panels, but an indirect sign will be increased fan noise or its complete absence. The defrost system consists of several key elements: Heating element (heater), defrost sensor and timer (or electronic control module).
If the heating element burns out or the sensor sticks, the ice stops melting and gradually blocks the air duct. The fan continues to circulate air, but it does not pass through the heat exchanger to the food. Repair in this case requires defrosting the unit during the day and replacing the failed element of the defrost circuit.
How to check the defrost heating element with a multimeter?
To check, you need to “ring” the heating element in resistance measurement mode. If the device shows infinity (break), it means that the heating element has burned out and requires replacement. Normal resistance varies depending on the power, usually 200-400 Ohms.
It is important to note that ignoring this problem leads to increased load on the compressor, which tries to compensate for the lack of cold by working hard. This may cause its early failure, which will entail costly repairs.
Malfunctions of the thermostat and temperature sensors
Another critical point of failure is thermostat (thermostat) or electronic temperature sensor. It is this unit that “tells” the compressor when to turn on and when to stop. If the thermostat contacts have oxidized or its bellows tube has lost its seal, the refrigerator may “think” that the chambers are already cold enough and not start the cooling cycle.
In models with electronic control, the temperature is controlled sensors. Failure of the refrigerator compartment sensor will result in the control module not sending a signal to open the solenoid valve or start the compressor for that circuit. In this case, the freezer can operate in normal mode if it has its own independent sensor or if the control system allows a local failure.
- 🔍 Symptoms: The compressor is silent, although it is warm inside, or, conversely, it works continuously, but does not cool.
- ❄️ Localization: Thermostats are often located inside the chamber under a plastic cover or outside on the case.
- ⚡ Check: Closing the thermostat contacts manually can start the motor, confirming its malfunction.
Replacement thermostat - a relatively simple procedure for mechanical models, but requiring precision. For electronic systems, it is often necessary to reflash the module or completely replace it, since sensors may give incorrect readings due to power surges in the network.
⚠️ Attention: When replacing a thermostat, it is important to install the capillary tube in exactly the same location where it was originally. A shift of even a couple of centimeters will lead to incorrect reading of the temperature and incorrect operation of the refrigerator.
☑️ Diagnostics of the thermostat
Clogged capillary tube or filter drier
One of the complex technical problems that causes the described symptom is clogging in the freon circulation system. The refrigerant moves through a very thin capillary tube, and any foreign substance - moisture, oxides, oil breakdown products - can clog the passage. Most often, a blockage forms at the entry point of the tube into the filter drier or in the filter itself.
If the blockage is partial, freon still circulates, but its pressure is not enough to cool the entire volume of the evaporator. As a result, the first section of the evaporator (usually in the freezer) is covered with frost, and then the tube remains warm. The refrigerator compartment at this time does not receive the required amount of refrigerant.
To eliminate this malfunction you need to:
- Release the remaining freon from the system.
- Replace the filter drier with a new one.
- Purge the system with nitrogen under high pressure to remove plugs.
- Evacuate the circuit and fill with new refrigerant.
It is impossible to carry out this procedure independently without special tools (vacuum pump, pressure gauge station, nitrogen cylinder). Attempts to “break through” the blockage by heating the filter with a blowtorch are dangerous and can lead to an explosion or complete failure of the system.
Refrigerant leakage (freon)
The most unpleasant reason for the owner is freon leak. The sealed circuit can be damaged by corrosion (especially in models with an evaporator sealed into the housing), mechanical stress, or due to factory soldering defects. When the amount of gas in the system drops, it is not enough for a full cooling cycle.
Leak symptoms often develop gradually. At first, the refrigerator starts working longer, then it turns on less often, but for a longer period. In the final stage, the freezer still somehow maintains minus temperatures, but the temperature in the refrigerator compartment is already above zero. Visually, you can notice swelling of the side walls or the appearance of rust in the foamed part.
Finding a leak is a labor-intensive process. The technician often has to open the foam layer to get to the evaporator tubes, or use special marker additives and ultraviolet lamps. If the leak occurs in the foam part, repair may not be economically feasible, since it requires replacing the entire internal box or installing an external evaporator (“weeping”).
| Type of fault | Probability | Difficulty of repair | Signs |
|---|---|---|---|
| Capillary clogged | Medium | High | Hot filter, cold condenser |
| Fault Heating element | High | Average | Ice in the chamber No Frost, noise |
| Freon leakage | High | High | Bloated walls, long idle time |
| Thermostat failure | Medium | Low | The motor does not turn on or does not turns off |
Problems with the fan and damper (for two-chamber models)
In refrigerators with a system No Frost and one compressor, the fan and air damper are responsible for the distribution of cold. If the fan that drives cold air from the freezer to the refrigerator compartment has stopped, then the cold remains below, and the upper compartment gets warmer.
The reasons for the fan stopping can be different: frosting of the blades, failure of the motor winding, or lack of power from the control module. The mechanical one that regulates the air flow also often breaks down. If it is stuck in the closed position, air simply does not flow into the refrigerator compartment. damperregulating air flow. If it is stuck in the closed position, air simply does not flow into the refrigerator compartment.
You can check the operation of the fan by opening the refrigerator door. In most models, when the door is open, the fan should stop (the limit switch is activated). If it does not work even when the door is closed, or makes a grinding noise, it needs to be replaced.
Faults of the compressor and start relay
Although the compressor is the “heart” of the refrigerator, and if it completely fails, nothing works, there are situations of partial malfunction. For example, loss of compression (worn valves) causes it to hum but not create enough pressure to circulate freon throughout the circuit. In this case, the freezer can maintain the temperature due to residual cold or low performance, but the refrigerator cannot.
Also often the culprit is starting relay. If it is faulty, the compressor may try to start, click and stall, or run on only one winding. This leads to overheating and emergency shutdown by the protection.
Diagnostics of the compressor requires measuring the outlet pressure and current. If the current consumption is below the rated value and there is no pressure, there is a loss of performance. If the current is high and the motor is humming, the mechanical part may be jammed.
⚠️ Attention: Replacing a compressor is one of the most expensive procedures. Before agreeing to repair, be sure to check the cost of the new unit and labor. Often for older models it is cheaper to buy a new refrigerator than to change the “motor”.
Frequently asked questions (FAQ)
Is it possible to use a refrigerator if it does not freeze, but the freezer is working?
Short-term use is possible for storing already frozen foods in the freezer, but storing perishable foods in It is strictly forbidden to use a warm refrigerator compartment. In addition, prolonged operation in this mode can completely “kill” the compressor.
How long does it take to defrost the refrigerator for diagnostics?
It takes at least 24 hours for complete defrosting and water to drain from the hidden channels of the No Frost system. A shorter defrosting may not eliminate the ice plug in the air ducts.
Why did the refrigerator work after defrosting, but after a week it stopped again?
This indicates that the reason is not the amount of ice, but the malfunction of the element that eliminates this ice (heating element, sensor, timer). Defrosting is a temporary measure; repairs are necessary.
Is it dangerous to change the freon in the refrigerator yourself?
Yes, it is dangerous and illegal without a license. Freon requires the correct type of oil, precise dosage and evacuation of the system. Residual air or moisture will lead to rapid failure of the compressor.
What to do if the refrigerator makes gurgling sounds?
Gurgling is the normal sound of freon flowing. However, if it is accompanied by a lack of cold, this may indicate airing of the system or a strong refrigerant leak.