Modern refrigerators Atlant with a No Frost system or full automatic defrosting cannot function without precise temperature control. A special electronic component is responsible for this process, which in technical documentation is often called a thermistor or temperature sensor. When this element fails, the unit stops responding correctly to changes in the thermal conditions inside the chambers, which leads to spoilage of food or freezing of the evaporator.
Independent replacement of this part is a very real task for a home craftsman, if you are careful and have a minimum set of tools. In this article, we will look in detail at where the sensor is located, how to safely dismantle it, and what to pay attention to when installing a new element. Correct diagnostics and care when working with wiring will allow you to restore the functionality of the equipment without calling a technician.
Before starting disassembly, you need to understand that sensors in different models Atlant can be located differently: in the evaporator area, on the back wall of the refrigerator compartment or in the control unit. Incorrect determination of the installation location can lead to damage to the plastic elements of the housing. Therefore, before starting work, you should carefully study the design of your specific unit.
Diagnostics of a thermistor malfunction
The first sign of failure temperature sensor is incorrect operation of the compressor. It can either work non-stop, trying to reach a non-existent low temperature, or not turn on at all, “thinking” that it’s already too cold inside. In models with electronic control, the alarm indicator often lights up on the display or the temperature symbol flashes, signaling a failure in the control system.
Another obvious symptom is the lack of periodic defrosting in No Frost systems. If you notice that the evaporator is overgrown with a “fur coat”, and the fan is humming, but no cold is coming in, the problem may lie in the fact that the sensor does not detect the accumulation of ice or does not give a signal to turn on the heating element. In some cases, the refrigerator begins to freeze to the point of a “glacier”, turning vegetables into ice blocks.
⚠️ Attention: Before starting any diagnostics, be sure to disconnect the refrigerator from the power supply. Working with electrical wiring and internal components under voltage is strictly prohibited and is dangerous to life.
To accurately check the resistance of the thermistor, you will need a multimeter. The sensor Atlant usually has a standard resistance at room temperature of about 4.6–5.5 kOhm (depending on the model). When cooled, the resistance should increase, and when heated, it should fall. If the device shows an open circuit or resistance that does not change with temperature, the part requires replacement.
The location of the sensors in different Atlant models
The structural location of the temperature sensors depends on the series of the refrigerator. In two-chamber models with one compressor, one main sensor is most often used to control the temperature in the refrigeration chamber, and a second one is responsible for the evaporator defrost cycle. In more complex systems, additional sensors can be installed to monitor the condition of the freezer.
In classic models Atlant the refrigerator compartment sensor is often hidden behind a decorative trim on the ceiling or side wall. You can get to it by removing the lampshade or protective panel. The defrost sensor, as a rule, is attached directly to the aluminum fin of the evaporator, hidden behind the rear panel of the freezer.
There are also models where the thermistor is built into the control unit or placed in a separate plastic cup. It is important not to confuse a temperature sensor with a defrost sensor, as they may have different resistance characteristics and wire lengths. Installing an unsuitable element will lead to incorrect operation of the automation.
Types of sensors in Atlant
In Atlant refrigerators, mainly two types of thermistors are used: with a resistance of 5 kOhm at 25°C and 10 kOhm at 25°C. They differ in the color marking of the tip or the length of the wire.
Required tools for replacement
Successful repair work does not require complex industrial equipment. A standard DIY kit is sufficient. The main thing is to prepare all the tools in advance so as not to interrupt the process of searching for the right screwdriver when some of the panels have already been removed.
You will need the following tools:
- 🔧 A set of screwdrivers (phillips and flat) for removing panels and fasteners.
- 🔪 Construction knife or scalpel for careful removal of insulation and stripping of contacts.
- 📏 Multimeter (tester) to check the resistance of the new and old sensor.
- 🧣 Electrical tape or heat-shrink tubes for sealing connections.
- 🔥 Hair dryer or lighter (for heat shrink) and soldering iron (if the connection is not a terminal connection).
Pay special attention to insulating materials. The inside of the refrigerator is an area of high humidity and temperature changes. Regular electrical tape can dry out and come off over time, which will lead to oxidation of the contacts and repeated failure. It is better to use high-quality heat shrink.
☑️ Preparation for repair
Step-by-step instructions for removing the sensor
The dismantling process begins with complete defrosting of the unit. Even if you replace the refrigerator compartment sensor, the presence of ice can make it difficult to access the interior panels or damage the wiring if you move it carelessly. Leave the refrigerator turned off for at least 10-12 hours.
After defrosting, remove all shelves, drawers and decorative trims that interfere with access to the desired area. If the sensor is on the evaporator, you will need to remove the back plastic panel in the freezer. The mounting screws are often hidden under plugs or located behind air dampers.
The thermistor itself is usually fixed in a metal sleeve or pressed with a clip to the evaporator. Remove it carefully. The sensor wire can be laid in a cable duct or simply glued to the housing. Do not pull the wire sharply so as not to damage the soldering points inside the sensor housing.
⚠️ Attention: The plastic of the internal panels of refrigerators Atlant in the cold becomes very fragile. Remove the fasteners only after complete defrosting, otherwise the plastic may crack.
If the sensor wiring is built into a common wiring harness and does not have a detachable connection, it will have to be bitten off. Leave some extra wire to connect to the new sensor. The old sensor is carefully removed from the seat, sometimes you need to turn it slightly.
Installing a new thermistor and connecting the wires
The new sensor must be installed in exactly the same place where the old one was located. This is critical for correct temperature reading. If the defrost sensor hangs in the air and is not pressed against the evaporator, the defrost cycle will not start on time, which will lead to freezing.
It is best to connect the wires by soldering, since the twists can oxidize and separate under vibration conditions of the compressor. After soldering, the joint must be insulated with heat-shrinkable tubing. The wire of the new sensor is laid along the same path as the old one and is fixed with standard clips.
The table below shows approximate resistance parameters for common sensors used in technology Atlant:
| Sensor type | Resistance at 25°C | Location | Tip color (approximate) |
|---|---|---|---|
| fridge compartment sensor | 4.6 - 5.5 kOhm | Ceiling or HK wall | Green / White |
| Defrost sensor (No Frost) | 6.4 – 7.2 kOhm | Freezer evaporator | Red / Black |
| Freezer compartment sensor | 5.0 - 6.0 kOhm | Freezer compartment | Blue |
After installing all the elements, reassemble the refrigerator in reverse order. Make sure that all panel latches click into place. Do not leave gaps through which warm air can enter the chambers.
Checking operation after replacement
Plug in the refrigerator and let it run in idle mode (without food) for 2-3 hours. During this time, the unit should reach temperature and turn off (or switch to temperature maintenance mode). Listen to the operation of the compressor: the on and off cycles should be rhythmic.
Pay attention to the indicators. If the malfunction icon disappears from the display and the temperature remains at the specified values, the replacement was successful. In models without a display, normal operation will be indicated by the absence of ice on the food and silence at night.
If after a day of operation you notice that the situation has repeated itself (the refrigerator does not turn off or does not freeze), then the problem is not in the sensor. In this case, the thermostat, control module could fail, or a freon leak could occur. Further diagnostics require more in-depth knowledge.
Is it possible to use a universal temperature sensor?
Theoretically, it is possible if you select an analogue with a similar resistance. However, “native” sensors Atlant have a specific wire length and body shape, which simplifies installation. Universal analogues may require extension of the wire, which creates extra connection points and potential risks of oxidation.
Why does the refrigerator freeze after replacing the sensor, but does not turn off?
This may indicate that the sensor is installed in the wrong place or has the wrong resistance. It is also possible that the problem was not in the sensor, but in sticky contacts of the thermostat or a malfunction of the compressor start relay. Repeated diagnostics are required.
Is it necessary to reset errors after replacing the sensor?
In most refrigerators Atlant errors are reset automatically after a reboot (disconnection from the network for 15 minutes). In some advanced models with complex electronics, you may need to enter the service menu to reset the error code, but this is rare for household series.