Sudden cessation of operation of the refrigeration chamber or, conversely, the transformation of products into ice blocks often indicates a failure in the system thermoregulation. Thermal sensor - these are the “eyes” and “ears” of your unit, telling the control unit the current temperature inside the chambers. If this element fails or transmits incorrect readings, the refrigerator stops responding correctly to changes, which can lead to food spoilage or compressor failure.
Understanding where this sensitive element is located is the first step to self-diagnosis. In modern models with the No Frost system and older two-chamber refrigerators, the location may differ significantly. where exactly where this sensitive element is located is the first step towards self-diagnosis. In modern models with the No Frost system and older two-chamber refrigerators, the location may differ significantly. The exact location of the sensor always depends on the specific model and type of defrosting system, so blindly copying actions without understanding the design can lead to damage to the evaporator.
In this article we will analyze in detail the architecture of refrigeration systems so that you could safely reach the required node. We will consider not only the physical location, but also methods for checking the serviceability of the element, as well as the nuances of replacing it. Safety When working with electrical appliances, this is priority number one, so it is absolutely impossible to ignore the rules for turning off the power.
⚠️ Attention: Before any manipulations inside the refrigerator, be sure to disconnect it from the power supply. Working with electrical components in a damp environment or under voltage is deadly and can damage electronics.
The principle of operation and the role of a temperature sensor in the system
A temperature sensor, or thermistor, is a semiconductor element whose resistance varies depending on the ambient temperature. Unlike old mechanical thermostats, which open the circuit when a certain point is reached, electronic sensors transmit a continuous stream of data to the main control module. This allows the system to maintain temperature conditions accurate to the degree.
The location of the element is dictated by the need to read the most representative data on the state of the air in the chamber. It is usually located in an area where the air flow is most stable, but is not exposed to direct contact with warm food immediately after loading. In models Indesit, Beko or LG engineers can choose different installation points, optimizing them for the design of the evaporator.
There are several types of sensors used in household appliances:
- 🌡️ Air sensors: monitor the overall temperature in the chamber and send a signal to turn on/off compressor.
- ❄️ Evaporator sensors: monitor the temperature of the cooling element, participating in defrost cycles (especially important for No Frost).
- 🧊 Ice maker sensors: detect ice formation or temperature in the ice storage area.
Incorrect operation of any of these elements leads to chaotic behavior of the refrigerator. It can freeze down to -30°C or run idle without dropping the temperature below +10°C.
⚠️ Attention: The design of refrigerators is constantly being improved. The location of the nodes in the 2026-2026 models may differ from earlier versions of the same series. Always check the manufacturer's official technical documentation before disassembling.
Location of the sensor in single-chamber refrigerators
In classic single-chamber models, where the freezer compartment is absent or is a small part of the main volume, it is usually easier to find a temperature sensor. Most often it is integrated into the control system or displayed on the internal wall. In older models with mechanical control, the role of the sensor is played by thermostat, the capillary tube of which passes inside the chamber.
In more modern versions with electronic control, the sensor is often hidden behind decorative panels on the ceiling of the refrigerator compartment or in a niche near the lighting lamp. This place was not chosen by chance: warm air rises, and it is there that temperature changes are felt most quickly. You can get to it by carefully removing the lamp shade or the top plastic cover.
Sometimes manufacturers, such as Atlant or Stinol, hide the sensitive element in a special hole in the back wall, which is closed with a plastic plug. To see it, you may need to remove the shelves and carefully inspect the perimeter of the back panel. In some cases, the sensor is built directly into the control unit, which is located outside, but its “probe” is inserted inside through a hole in the housing.
Where to look for the sensor in two-chamber models and No Frost
In two-chamber refrigerators the situation is complicated by the presence of a separate freezer and often - forced air circulation systems No Frost. There may be two, three or even more thermal sensors here. The main refrigerator compartment sensor is usually hidden in the rear, often behind a decorative panel that covers the air ducts. You can remove it by snapping the latches or unscrewing the hidden screws.
In the freezer compartment of the No Frost system, the evaporator temperature sensor is often located directly on the evaporator itself, which is hidden behind the back wall. To get to it, you will have to dismantle the entire back panel of the freezer, which requires care, since the fans and defrost heaters are also located there. The sensor can be fixed to the aluminum tube of the evaporator using a special clamp or inserted into a socket.
Let's consider the main locations depending on the brand:
- 🔹 Samsung: the sensor is often hidden in the upper part of the rear wall of the refrigerator compartment, sometimes it is accessible after removing the plastic duct cover.
- 🔹 LG: in models with linear compressor sensors can be built into the air supply channels; partial disassembly of the internal casing is required.
- 🔹 Bosch/Siemens: Combined units are often used, where the sensor is mounted on the inside of the rear panel, access to which can be accessed from inside the chamber.
If it is located incorrectly or is damaged during installation, the system will not turn on the heater, and the evaporator will become overgrown with a “fur coat” that blocks air circulation.
Location table sensors by brand
To simplify your search, we suggest that you familiarize yourself with the summary table, which shows the typical location of temperature sensors in popular brands of refrigerators. Remember that there may be design differences within the same line.
| Refrigerator brand | Typical sensor location | Difficulty of access | Features |
|---|---|---|---|
| Indesit | Inside the chamber, on the back wall or in corner under the plastic | Low | Often accessible without complete disassembly |
| LG | Behind the back panel in the freezer (No Frost) or in the air duct | Medium | Requires panel removal evaporator |
| Samsung | In the upper part of the rear wall or in the control unit | Medium | Many models with remote sensors |
| Atlant | In a niche under the lamp or in the channel behind the rear wall | Low/Medium | Simple design, easy to diagnose |
| Electrolux | Built into a plastic case on the back wall | High | Often requires dismantling the entire internal sheathing |
This table is for reference only. The actual situation may differ depending on the year of manufacture and the specific modification. If you are not confident in your abilities, it is better to contact a professional technician.
Diagnostics and checking the serviceability of the temperature sensor
Before disassembling half of the refrigerator in search of a replacement, you need to make sure that the problem lies in the sensor. Symptoms of a malfunction may be similar to a compressor failure or a freon leak. Main symptoms: the refrigerator does not turn off, runs cyclically with very short pauses, or does not start at all, showing an error on the display.
To check you will need multimeter. First you need to find the sensor (using the knowledge from the previous sections) and disconnect its connector from the control board. Then switch the multimeter to resistance measurement mode (Ohm). At room temperature (about 20-25°C), a working sensor usually shows a resistance in the range from 2 to 10 kOhm, depending on the model.
A more accurate method is to check at different temperatures. Place the sensor (disconnected) in a glass of water and ice (about 0°C) or, alternatively, heat it. The resistance should change smoothly. If the multimeter shows a “break” (infinity) or “short circuit” (zero), or the readings do not change when the temperature changes, the element is faulty.
☑️ Checking the sensor with a multimeter
Replacement process and important nuances
If the diagnostics confirm a malfunction, the sensor must be replaced. You should buy an original spare part or a high-quality analogue with an identical nominal resistance. Installation “by eye” or using a sensor with other parameters will lead to incorrect operation of the entire unit. The replacement process is usually the reverse of the search process: get to the unit, carefully disconnect the old element and install a new one.
Pay special attention to tightness. The entry point of the wiring into the chamber or evaporator area must be carefully sealed so that moist air does not penetrate into the structure and cause corrosion or freezing. Use special sealant or heat shrink tubing. The wires should not touch the moving parts of the fan or hot surfaces.
After assembling and connecting the refrigerator to the network, the system may require time for calibration. Do not load food into the chamber immediately. Let the unit run idle for 2-3 hours so that it reaches the specified mode and “sees” the new sensor. If the error on the display does not disappear, perhaps the problem is not in the sensor, but in the control board.
Is it possible to temporarily operate a refrigerator with a faulty sensor?
Technically, it is possible if you connect the circuit directly or use a snag, but this is highly not recommended. Without temperature control, the compressor can operate continuously, which will lead to its overheating and failure, or the products in the chamber will deteriorate due to insufficient or excessive cold.
Why didn’t the new sensor correct the situation?
There may be several reasons: the resistance value is incorrectly selected (the sensor does not fit the model), the problem lies in a broken wiring between the sensor and the board, the control module itself is faulty, or the diagnosis was made incorrectly (for example, freon leak).
How often should the temperature sensor be changed?
The service life of the temperature sensor is usually 5-10 years or more. It is not a consumable item and is replaced only when it fails. However, under conditions of constant voltage drops or high humidity, it may degrade faster.
Does the type of refrigerant affect the location of the sensor?
The type of refrigerant (R600a, R134a) does not have a direct effect on the location of the sensor. The location is determined by the camera design and control system. However, in refrigerators with R600a (isobutane) the fire safety requirements for soldering are higher, but this concerns circuit repair, not replacement of electronics.