The situation when the upper part of the refrigerator continues to cool food, but the lower chamber suddenly stops freezing, is familiar to many owners of household appliances. This may happen suddenly, without any prior audible warning, or it may be the result of a gradual decrease in the efficiency of the unit. In most cases, users are faced with the fact that ice melts in the freezer compartment, and food begins to deteriorate, while in the refrigerator compartment the temperature remains normal.
The reasons for such an imbalance can be either trivial, associated with improper operation, or serious technical malfunctions requiring specialist intervention. No Frost System, which is installed in most modern models today, has a complex structure air circulation, where the failure of one element disrupts the operation of the entire circuit. Understanding the principles of operation of the compressor and evaporator will help you quickly navigate the problem.
Before calling a technician, it is necessary to conduct an initial diagnosis to eliminate simple errors. Often the problem is solved by properly defrosting or adjusting the thermostat. However, ignoring the symptoms can lead to the failure of an expensive compressor. Let's look at the main factors influencing the temperature regime of the lower chamber.
Violation of operating rules and simple reasons
Often the answer to the question why the lower chamber stopped working lies not in the breakdown of parts, but in the actions of the user himself. The most common mistake is putting too much warm food in the freezer. When you load a large batch of meat or berries at room temperature into the chamber, compressor begins to work at the limit of its capabilities, trying to cool the internal volume.
If the system cannot cope with the load, the sensors may get stuck in the defrost mode or simply not give a command to turn on the cooling, considering the temperature sufficient. It is also worth checking the tightness of the door. Rubber seal over time dries out or becomes dirty, letting warm air in.
⚠️ Attention: If you notice that the door of the lower chamber does not close tightly, do not ignore it. The constant flow of warm air leads to the formation of an ice coat on the evaporator, which blocks the circulation of cold.
Another factor may be installing the refrigerator too close to a wall or heat source. Condenserlocated at the back must effectively transfer heat to the environment. If ventilation is impaired, the efficiency of the entire system decreases, and this primarily affects areas remote from the evaporator or the freezer, depending on the design.
Check that the ventilation holes inside the chamber are not blocked by food. In models with the system Total No Frost cold air is pumped by a fan and distributed through the channels. If these channels are clogged with bags or containers, the cold simply does not reach the sensors and products.
Problems with the defrosting system and sensors
In modern refrigerators, the process of ice formation on the evaporator is controlled automatically. It turns on periodically Defrost heating element, which melts the ice, and the water flows into the drain pan. If this cycle is disrupted, the evaporator becomes overgrown with an ice shell, which blocks the operation of the fan and the air passage.
Most often the culprit is the defrost sensor. This small element controls the temperature of the evaporator. If it fails and shows incorrect data, the control board may simply not “know” to turn on the heat to remove ice. As a result, the lower chamber stops freezing due to an ice plug.
How to check the defrost sensor?
To check the defrost sensor, you need a multimeter. At room temperature, the resistance of a working sensor should be close to zero (closed) or have a certain value depending on the model. If the device shows a break, the element requires replacement. defrost mode, or, on the contrary, does not exit it, starting to heat the chamber instead of cooling.
Diagnostics often require partial disassembly of the back wall of the freezer, which is best left to professionals to avoid damaging the fragile plastic latches and air ducts.
It is also worth mentioning the defrost timer or control module, which regulates the operating cycles. Failures in the electronics lead to the fact that the refrigerator either does not enter the defrost mode at all, or, conversely, does not exit it, starting to heat the chamber instead of cooling.
Fan malfunctions and air circulation
In refrigerators with forced air circulation (No Frost), the fan is responsible for the distribution of cold. If this unit stops working, cold air remains in the evaporator zone (usually behind the back). wall), but visually it may look like this: the refrigerator is humming, the compressor is running, but it is warm in the lower chamber.
The reasons for the fan stopping can be different:
- ❄️ Freezing the blades are due to ice, which mechanically blocks rotation.
- 🔌 Breakage of wiring or oxidation of contacts going to the fan motor.
- ⚙️ Wear of bearings or bushings, which leads to shaft jamming.
- 💥 Winding combustion fan motor.
To check the fan, it is often enough to remove the back panel in the freezer. When the door is open, many models automatically turn off the fan (the limit switch is activated), so to check, you may need to press the door button or use a magnet to simulate closing.
The absence of fan hum when the compressor is running is a sure sign. its malfunction. In this case, the products in the lower chamber stop freezing, although in the upper part of the refrigerator the temperature can be maintained due to natural convection or a separate circuit.
Refrigerant leakage and problems with the compressor
The most serious reason why the lower chamber does not work is a leak. freon. The refrigerant circulates in a closed circuit, and if a microcrack appears in the tubes or connections, the gas gradually evaporates. First, the performance drops, and the refrigerator begins to work longer, and then stops freezing altogether.
In two-compressor models, the leak can be localized in the circuit of the lower chamber. In single-compressor systems with one. In the evaporator, the lack of freon leads to the fact that there is not enough of it for the entire cycle, and the cold simply does not reach the end of the system. The compressor can work continuously, trying to gain temperature, and become very hot.
| Symptom | Probable cause | Necessary actions |
|---|---|---|
| The compressor works constantly | Freon leak or clogged capillary | Call a technician to find a leak |
| The compressor is silent, there is no light | Problem with the electrics or starting relay | Checking voltage and relay |
| A gurgling sound is heard | Normal circulation or lack of freon | Observation or diagnostics |
| Hot condenser at the back | Normal operation or contamination | Cleaning the grill from dust |
Freon leakage is dangerous not only for food damage, but also for the risk of compressor failure. Working idling or in abnormal mode, the motor can burn out, which will require an expensive replacement of everything. unit. The tightness of the system is a key factor in the longevity of the refrigerator, and any signs of oil stains on the tubes require immediate attention.
Clogged capillary tube
The capillary tube is a thin copper pipe that acts as a choke in the system, creating a pressure differential between high and low pressure. Over time, blockages may form inside it due to paraffin plugs (oil oxidation products) or the ingress of moisture, which turns into ice slush.
If clogged, refrigerant circulation is disrupted. Freon cannot move freely along the circuit, and cooling stops. A characteristic sign of such a malfunction is that the compressor operates with overload, gets very hot, and then is turned off by the thermal protection relay.
To eliminate this problem, it is necessary to evacuate the system, replace the filter-drier and refill with refrigerant. It is impossible to carry out this procedure independently without special equipment (vacuum pump, pressure gauge station, scales).
Failures in the electronic control module
Modern refrigerators are controlled by electronic boards that receive signals from many sensors. If control module fails, it can send incorrect commands to the actuators. For example, not turning on the compressor when necessary, or not starting the fan.
Voltage surges in the network are often the cause of failures. Even if the refrigerator looks good on the outside, tracks or relays inside the board could have burned out. In some cases, a reboot helps - disconnecting the device from the network for 15-20 minutes.
⚠️ Attention: Electronic modules are sensitive to humidity. If you flooded the refrigerator with water when washing it, moisture could get onto the circuit board, causing a short circuit. In this case, it is strictly forbidden to turn on the device before drying.
Diagnostics of the module requires testing the elements and checking the output signals. If you notice that the display lights up incorrectly, blinks or displays errors (fault codes), most likely the problem lies in the “brains” of the device.
FAQ: Frequently Asked Questions
Can I continue to use the refrigerator if the lower chamber does not freeze?
Short-term use is possible for storing food in the upper compartment, but you cannot leave the equipment in this condition for a long time. An idling compressor may burn out and the products in the lower chamber may deteriorate. In addition, if the cause is a leak, air and moisture may enter the system, which will complicate and increase the cost of repairs.
How long does defrosting take to restore operation?
Usually 12-24 hours of complete defrosting with the doors open is enough. This is necessary so that the ice in the hidden channels and on the evaporator completely melts. Do not try to speed up the process with a hairdryer or hot water - a sharp temperature change can damage the plastic and evaporator tubes.
Why, after defrosting, did the lower chamber stop freezing again after a week?
This is a sure sign of a malfunction of the defrosting system. Most likely, the heating element, defrost sensor or timer burned out. Ice builds up again on the evaporator and blocks the air flow. The faulty element of the defrost system needs to be replaced.
Does the room temperature affect the operation of the lower chamber?
Yes, it does significantly. If the refrigerator is in an unheated room at a temperature below +10°C, the oil in the compressor thickens and it may not start. Also, in such conditions, the temperature sensor in the refrigerator compartment may not work correctly, which is why the compressor does not turn on and the freezer stops freezing.