The situation when you open the door of a household appliance and feel warmth instead of the expected cold always causes panic. Products begin to deteriorate, and thoughts immediately arise in your head about expensive repairs or buying new equipment. However, before calling a technician or running to the store, it is worth carrying out an initial diagnosis, since in many cases the problem lies in trivial things that can be fixed on your own.
Modern refrigeration units, be it Indesit, Bosch or LG, are complex systems where the failure of one element affects the operation of the entire circuit. Insufficient cooling can be caused by a dozen different factors: from incorrectly set temperature to a serious refrigerant leak. Understanding the principle of operation will help you quickly identify the culprit of the malfunction.
In this article we will analyze in detail the main reasons why the refrigerator stops freezing, and we will create an action algorithm for each case. You will learn how to distinguish a software failure from a mechanical failure, and understand in which cases independent repair is safe, and when it is better not to risk it.
External factors and operating errors
Before disassembling the equipment, it is necessary to exclude the simplest and most obvious causes. Users often forget that a refrigerator is not just a cabinet, but an active device that requires certain operating conditions. First of all, check if the door is tightly closed. If the rubber seal is worn out, dirty, or simply does not fit due to an object falling in, warm air constantly flows inside.
It is also worth paying attention to the location of the unit. If it stands close to the wall or in a niche without gaps, heat transfer is disrupted. The compressor overheats and goes into protection mode, stopping pumping freon. Make sure that the required gap of 5-10 centimeters is left at the back and sides.
⚠️ Attention: Never try to forcefully slam the door if it does not close. This can lead to deformation of the hinges or damage to the plastic shelves on the door. First, find and remove the obstacle.
Another common factor is loading with hot products. If you just put a large pot of soup into the chamber, the thermostat may not have had time to react, and the compressor is working hard trying to cool the entire volume. In this case, it is enough to wait several hours until the system enters operating mode.
- 🔍 Check the tightness of the rubber seal around the entire perimeter of the door.
- ❄️ Make sure that there is a gap between the back wall of the refrigerator and the wall of the room.
- 🍲 Do not place hot foods inside, let them cool to room temperature.
- 🌡️ Check that the ventilation holes inside the chambers are not blocked by food.
It is also important to check the settings. Perhaps one of the household members accidentally changed the operating mode or turned on the fast freezing function, which should turn off itself after a certain time, but due to an electronics failure this did not happen. Reset the settings to factory values through the control panel.
Problems with the thermostat and temperature sensors
If external factors are excluded, the next in line is the temperature control system. In older models, mechanical sensors (thermistors) are responsible for this, and in modern ones - electronic sensors (thermistors). They are the ones who give the command to the compressor to turn on or off. If the sensor is “lying” and shows that the chamber is already -20°C, although it is +5°C, the motor simply will not start. thermostat, and in modern ones - electronic sensors (thermistors). They are the ones who give the command to the compressor to turn on or off. If the sensor “lies” and shows that it is already -20°C in the chamber, although it is +5°C there, the motor simply will not start.
Diagnostics of a mechanical thermostat is often carried out by the method of elimination. In some models, you can temporarily close the regulator contacts. If after this procedure the refrigerator “came to life” and began to freeze, then the problem is in this unit. Replacing a thermostat is a simple and inexpensive procedure.
How to check a thermostat with a multimeter?
To check, remove the regulator and ring its contacts. At room temperature the circuit should be closed. If the multimeter shows a break, the part is faulty and requires replacement. You can also lower the sensitive tube of the thermostat into cold water with ice - after a few minutes you should hear an opening click.
In units with a system No Frost air dampers often fail. They regulate the flow of cold air from the freezer to the refrigerator compartment. If the damper is stuck in the closed position, the main chamber will be warm, despite the fact that there is ice in the freezer.
Electronic control modules can also fail. Power surges in the network sometimes lead to the board freezing or failure of specific elements responsible for reading temperature readings. In such cases, it may be necessary to reflash or replace the control board.
- 🛠️ Check the integrity of the capillary tube of the mechanical thermostat.
- 📉 Diagnose the thermistors using a multimeter (resistance should change when heating/cooling).
- ⚙️ Inspect the air damper mechanism for mechanical obstacles.
- 🔌 Try unplugging the appliance for 15-20 minutes to reboot the electronics.
Faults in the compressor and start relay
The heart of any refrigerator is the compressor. If it does not start, hums but does not pump, or starts for a couple of seconds and immediately stalls, the problem lies in the motor or its starting system. The most common and easily removable reason is failure starting relay. This is a small part that supplies a starting impulse to the motor windings.
You can determine a relay malfunction by a characteristic click when you try to start and subsequent silence. Sometimes the relay can be carefully removed and shaken: if the ringing of broken parts is heard inside, it needs to be replaced. Fortunately, this part is inexpensive, and you can replace it yourself by choosing an analogue according to the marking.
⚠️ Attention: Before any manipulations with electrical components, be sure to unplug the refrigerator from the outlet. Residual voltage or an accidental short circuit can be life-threatening.
A more serious problem is the compressor wedge. This happens when the piston group gets stuck due to exhaustion, lack of lubrication or foreign particles. In this case, the motor hums, trying to turn over, but the shaft stands still. Attempts to “reanimate” it by increasing the voltage or knocking usually give only a temporary effect.
It is also worth mentioning the interturn short circuit in the motor windings. In this case, the compressor may hum quieter than usual or, conversely, become very hot, and the current consumption will differ from the nominal one. Diagnostics requires special knowledge and tools, so you can’t do without a technician.
The table below will help you navigate the symptoms of a compressor group malfunction:
| Symptom | Probable cause | Difficulty of repair |
|---|---|---|
| Silence, no hum | Open circuit, faulty thermostat or relay | Low |
| Humming for 5-10 seconds, then a click and silence | Faulty starting relay or wedge compressor | Average |
| Works constantly, without turning off | Freon leakage, compressor wear, bad seal | High |
| Extreme heating of the housing motor | Interturn short circuit, overload | High (replacement) |
☑️ Compressor diagnostics
Freon leakage and capillary blockage systems
Refrigerant (freon) is a working fluid that circulates through the system, taking away heat. If a microcrack has formed in the circuit, the gas gradually evaporates. At first, the refrigerator begins to freeze worse, then it stops turning off, trying to gain temperature, and in the end it simply goes silent, since there is not enough pressure to operate.
Signs of a leak can often be seen visually. If you see a bulge in the rear metal wall (where the capacitor is sealed) or, conversely, strange oily spots under the unit, this is an alarming sign. Also, a uniform layer of frost may not form on the evaporator, but only a separate area.
Clogged capillary tube is another reason why freon cannot circulate. An ice or dirt plug forms in the system, blocking the flow of refrigerant. The symptoms are similar to a leak: the compressor works, but there is no cold. Sometimes defrosting for a day helps if the plug is icy, but more often it is necessary to flush the system with nitrogen and replace the filter-drier.
Repair in the event of a leak or blockage requires special equipment: a vacuum pump, a pressure gauge station and a freon cylinder. It is almost impossible to carry out this work efficiently on your own, since sealing the circuit and precise dosage of the refrigerant is required.
- 🌬️ Look for oily marks on the pipes and joints - freon comes out along with the oil.
- 🧊 Pay attention to uneven freezing evaporator.
- 👂 Listen to the characteristic sound of flowing liquid (gurgling), which should not normally be present.
- 🔧 Remember that repairs require a license and equipment for working with gases.
Icing of the No Frost system
In refrigerators with a system No Frost a special timer and heating element (heating element) are responsible for removing moisture and defrosting the evaporator. If this system fails, the evaporator becomes overgrown with a “coat” of ice, which blocks the channels for supplying cold air to the chambers. As a result, the fan hums, but air does not pass through, and the food spoils.
Most often, the defrost heating element itself burns out or the defrost sensor, which is supposed to record the temperature of the evaporator and turn off the heater, fails. The defrost timer may also jam, causing the refrigerator to go into perpetual freezing mode without defrosting cycles.
You can diagnose the problem by completely defrosting the refrigerator (turn it off for 24 hours with the doors open). If after turning it on it starts to freeze normally, but after 1-2 weeks the problem returns, it means that the defrosting system is faulty and requires replacement of components.
⚠️ Attention: Do not use sharp objects (knives, screwdrivers) to chip ice inside the chamber. You can break the freon channels or damage the fan, which will lead to expensive repairs.
In some models, ice can block the fan itself. If the blades are frozen to the housing, the fan motor may burn out or be overloaded. When defrosting, be sure to check whether the fan rotates freely manually.
Frequently asked questions about refrigerator repair
In this section we will answer the most popular questions that arise among owners of refrigeration equipment when faced with cooling problems.
Why does the refrigerator work, but the upper chamber does not freeze?
Most often this indicates a problem with air circulation. In two-compressor models, one of the compressors or the upper chamber thermostat could fail. In single-compressor systems (especially No Frost), the air supply channel could become clogged or the damper could fail. A freon leak is also possible when the pressure is only enough for the freezer.
How long should the refrigerator cool down after defrosting?
After complete defrosting and turning on, the unit takes time to reach operating mode. This usually takes from 2 to 4 hours. During this time, you should not load products. If after 5-6 hours the temperature does not drop, then there is a technical malfunction.
Is it possible to use a refrigerator if it does not freeze well?
Using equipment in this mode is not recommended. The compressor will run non-stop, trying to reach the set temperature, which will lead to overheating and rapid wear. In addition, bacteria can begin to multiply in insufficiently cooled products, which is dangerous to health.
Why did the refrigerator stop freezing again after a month after replacing the freon?
This is a classic sign of poor-quality repairs. The technician had to find the leak, solder it, and only then refill the system. If you simply add gas to a leaky circuit, it will inevitably escape again. A repeated call to the technician is required for full diagnostics and soldering.
What to do if there is a burning smell in the refrigerator?
If you smell a burning smell, immediately unplug the appliance. This may indicate overheating of the wiring, melted insulation, or an interturn short circuit in the compressor. The operation of such a device is a fire hazard.