The situation when the lower chamber of the refrigerator turns into a block of ice, and in the upper compartment the products begin to deteriorate, 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. Most often, the problem lies not in the fact that the cold has “ended”, but in the fact that it has stopped flowing where it should be, or cannot be removed from the evaporator.
It is important to understand that modern units, whether Indesit No Frost or classic Atlant with a drip system, use different operating principles, but the physics of the cooling process united. The compressor builds up pressure, the freon evaporates, taking away heat, and returns back. If this cycle is disrupted at any stage, the upper chamber, which is often cooled by cold air rising from below or circulating through a separate circuit, ceases to receive the necessary cold.
In this article we will analyze in detail the mechanical and electrical causes of the malfunction. We will not guess from the coffee grounds, but will look at specific components: from the thermostat to the compressor, so that you can accurately determine the nature of the breakdown and understand whether you need to call a technician or the situation can be corrected yourself.
Impaired refrigerant circulation: leakage and blockage
The most common technical reason that the freezer is working and the refrigerator compartment is no, it is a partial leak of freon or a blockage of the capillary tube. The system contains a strictly defined amount of refrigerant under pressure. If a microcrack occurs in the circuit, the pressure drops, and the freon simply does not reach the evaporator in the upper compartment, ending its cooling cycle already in the freezer.
Clogging of the capillary tube often occurs due to moisture that has entered the system during poor-quality repairs, or decomposition products of the compressor oil. A so-called “ice plug” or mud blockage is formed. In this case, the compressor works almost without interruption, trying to build up pressure, but the refrigerant stays at one point. You may notice that the condenser (grid at the back) is only partially hot or, conversely, cold, which indicates a lack of circulation.
⚠️ Attention: If you hear a characteristic hissing or gurgling sound when the unit is operating, this is a sure sign of a leak. Under no circumstances try to solder tubes yourself without a vacuum pump and professional equipment - you will only aggravate the situation by driving air and moisture into the system.
Diagnostics of leaks at home is limited to visual inspection and listening. If the compressor is hot and the tubes coming out of it are at different temperatures (one hot, the other lukewarm or room temperature), this indicates a pressure problem. It is also worth checking for oily stains on the floor under the equipment or on the back wall - oil often escapes along with the gas through the depressurization area.
Faults of the thermostat and temperature sensors
The refrigerator electronics rely on sensor readings. If the thermostat (thermostat) fails, it may “think” that the chamber is already cold enough and turn off the compressor ahead of time. As a result, the freezer, which has a smaller volume and better insulation, still retains cold, and the upper compartment heats up quickly. In older models with mechanical control, the thermostat capillary tube itself, which runs inside the housing, often breaks.
In models with a system No Frost and electronic control, air sensors are responsible for the temperature. If the refrigerator compartment sensor “lies” and shows that it is +2°C, although in fact it is +10°C, the controller will not give the command to cool. Often such sensors fail due to oxidation of the contacts or power surges in the network.
To test a mechanical thermostat, you can conduct a simple experiment: disconnect the device from the network, remove the thermostat and close its contacts directly (if you are confident in your electrical skills). If after turning on the compressor starts working and it gets cold, then the problem is in the sensor. However, with electronic sensors everything is more complicated - their resistance needs to be checked with a multimeter at different temperatures and checked with the resistance table for a specific model.
Problems with the defrosting system in No Frost refrigerators
Owners of units with the system No Frost face the described problem regularly. The operating principle of such models is based on the circulation of cold air from the evaporator, which is hidden behind the back wall of the freezer. If the automatic defrosting system fails, a “coat” of ice builds up on the evaporator. This ice blocks the channels through which cold air should flow into the upper compartment.
As a result, the fan moves the air, but it cannot break through the ice jam to the refrigerator compartment. At the same time, the freezer can freeze even more than usual, since the cold does not go away anywhere. Over time, there is so much ice that it begins to put pressure on the walls or even jams the fan, which is accompanied by a characteristic crackling or humming.
Three main elements are responsible for the defrosting system:
- ❄️ Heating element defrost —a heating element that is periodically turned on to melt the ice on the evaporator.
- ⏱️ Defrost timer (or electronic module) - a device that counts the intervals of compressor operation and starts the defrost mode.
- 🌡️ Thermofusion (defrost sensor) - a sensor that turns off the heating element when the ice has melted, so as not to overheat the system.
Most often the heating element itself burns out or the thermofusion fails. You can check the heating element with a multimeter for an open circuit. If the resistance is infinitely high, the element is faulty. It is also worth inspecting the drainage hole: if it is clogged with debris (food debris, mold), the melt water does not drain, freezes and blocks the system.
The hidden danger of frequent defrosting
Many users begin to defrost the refrigerator manually every two weeks, seeing ice. This temporarily solves the problem, but hides the real problem. Constant operation of the heating element or its absence leads to moisture entering the electrical contacts, causing corrosion and short circuits, which can ultimately damage the main control module.
Failure of the compressor and start relay
The compressor is the heart of the refrigerator. If it does not work at full capacity or turns off too often, the freon pressure is not enough to fully cool the two chambers. Often the culprit is the start relay. This device protects the motor and helps it start. If the relay is stuck or burnt out, the compressor may hum, click, but not start, or only start for a few seconds.
In some cases, there is a situation where only one cooling circuit is working (usually the one that goes to the freezer), if the model provides for separation. This may be due to a malfunction of the solenoid valve that switches the refrigerant flow. If the valve is stuck in the closed position for the upper circuit, the cold simply will not flow there.
Signs of problems with the compressor group:
- 🔊 Loud knocking or clanging at startup - a sign of mechanical wear or a problem with the motor suspension inside the casing.
- 🔥 Strong heating of the case compressor (impossible to touch with your hand for more than 2-3 seconds) - indicates an overload or inter-turn short circuit of the windings.
- ⚡ Knocking out plugs or the circuit breakers in the panel when the refrigerator is turned on is a clear sign of a short circuit in the compressor circuit.
⚠️ Attention: If the compressor operates continuously for more than 24 hours without shutting down, this is an extreme operating mode. In this case, you must immediately disconnect the device from the network and let it cool for at least 5-6 hours before restarting, otherwise the motor will burn out completely.
Mechanical damage and problems with seals
The reason does not always lie in complex electronics or gas. A simple violation of the seal of the chamber leads to the fact that warm, moist air constantly enters inside. The cooling system tries to compensate for heat loss and works hard, but the upper part, where the door opens most often, simply does not have time to cool down. The main enemy here is the rubber door seal.
Over time, rubber becomes tanned, cracks or deforms. Air penetrates into microscopic cracks. The seal can also become contaminated with sticky food residues, which prevents a tight seal. You can check the tightness using a regular sheet of paper: clamp the sheet between the door and the body around the perimeter. If the sheet is pulled out without resistance, the seal does not hold.
Comparison of symptoms of different malfunctions:
| Symptom | Probable cause | Characteristic symptom |
|---|---|---|
| The freezer is freezing, the top warm | Freon leak / Capillary clogged | The compressor runs without stopping, the condenser is cold or partially warm |
| Ice on the back wall of the freezer | No Frost system malfunction | Lack of air circulation, ice plug in the channel |
| The cold disappears periodically | Thermostat malfunction | The compressor turns on rarely or does not turn on at all |
| Clicks and buzzing without start | Start relay / Compressor | Short cycles of motor operation, casing overheating |
In addition to the seals, it is worth checking the door hinges. If they are loose, the door warps and does not fit tightly, even if the rubber band is intact. Adjusting the hinges often solves the problem of “escaping” cold without replacing expensive parts.
Self-diagnosis algorithm
Before calling a technician, it is useful to conduct an initial diagnosis in order to approximately understand the scale of the problem and the cost of repairs. Start by completely defrosting the refrigerator. Leave it turned off with the doors open for at least 24 hours (preferably two days). This is necessary so that all the ice melts, even in the hidden channels of the system No Frost.
After defrosting, turn on the device without food. Wait 1-2 hours. If cold appears in both the upper and lower chambers, and then disappears again after a few days, the problem is definitely in the defrosting system (heating element, timer, sensor). If the cold does not appear at all or freezes only at the back wall of the freezer, there is likely a leak or blockage.
☑️ Primary inspection checklist
Pay attention to behavior of the compressor in the first minutes after switching on. It should start confidently, without long beeps or clicks. The vibration should be uniform. If you observe strong vibration, check whether the refrigerator tubes are touching each other or the body - sometimes simply moving the tube away with your hand (with the appliance turned off!) is enough to eliminate the rattling.
When you need to call a professional technician
There are a number of malfunctions that cannot be fixed at home without special tools. If the diagnostics indicated a freon leak, a clogged capillary system, or a compressor breakdown, a technician is needed. This work requires a vacuum pump, a pressure gauge station, a supply of freon, a torch and solder. Independent attempts to fill the refrigerator with a “spray can” from a car dealership will lead to damage to the compressor, since domestic refrigerators use special oils and precise dosages of refrigerant.
It is also worth contacting a specialist if the problem lies in the electronic control module. Resoldering capacitors or replacing triacs requires skills in working with a soldering station and knowledge of circuit design. Unprofessional repair of electronics often leads to the entire unit burning out, which is much more expensive.
Do not forget that most brands (LG, Samsung, Bosch, Liebherr) have warranties. If your refrigerator is less than 3-5 years old (the period depends on the brand and unit), warranty repairs may be free. However, if you break the seals or try to replace the thermostat yourself, warranty service will be denied.
Prevention and proper operation
To avoid a recurrence of the situation, it is important to follow the operating rules. Do not put hot food in the refrigerator - this creates excess humidity and stress on the compressor. Make sure that food does not block the ventilation holes (especially in systems No Frost), otherwise air circulation will be disrupted locally and the upper part of the chamber will stop cooling.
Regularly, at least once every six months, check the cleanliness of the condenser at the back. If you have pets, fur can clog the grille, creating a “fur coat” of dust, which impairs heat transfer. The compressor begins to work longer and harder, trying to compensate for the poor (heat transfer), which reduces its resource.
Why does the refrigerator not freeze for a long time after defrosting?
After a long defrosting (more than 24 hours), the oil in the compressor needs time to return to working condition and be distributed throughout the system. In addition, the walls of the chamber and the food (if you have already loaded it) must cool down. The normal time to enter the mode is from 2 to 6 hours. If after 10-12 hours the cold does not appear, it means that defrosting did not help and the reason is deeper.
Is it possible to use a refrigerator if only the freezer freezes?
You can use it in this mode for a short time (1-2 days) while you are waiting for a repairman or spare parts. However, the compressor will work non-stop, which will lead to overheating and increased energy consumption. Food in the upper chamber can spoil, even if visually they look normal.
How often do you need to defrost a No Frost refrigerator?
Technically, the system No Frost does not require defrosting to remove ice, as it does it itself. However, once every 1-2 years it is recommended to carry out a complete defrosting and washing for hygienic purposes, removing odors and cleaning the drainage hole, which can become clogged with mold or crumbs.
What to do if there is water in the refrigerator, but it is freezing?
If there is water in the lower part of the refrigerator compartment, but there is cold, the drainage drain is most likely clogged hole. It is located on the rear inner wall, often under a plastic cover. You can clean it using a soft wire or a special brush, pouring a little warm water into it.