A modern refrigerator is a complex unit where each element is responsible for the safety of your products. Cold sensor is one of the key components on which the correct operation of the cooling system depends. If the chamber becomes too warm or, conversely, the food begins to become covered with an icy crust, the problem often lies in this unit. Understanding its location will help you quickly diagnose a malfunction or decide to call a repairman.
In most cases, the user does not even suspect where exactly this important element is hidden. Thermostat or the electronic sensor can be hidden behind plastic panels or built into the evaporator. Engineering Manufacturers are constantly changing, and if in old models everything was in plain sight, then new ones require a deeper immersion into the device. Let's figure out how to find this component in various types of refrigeration units.
Before you start disassembling, it is important to understand the basic principle of operation. Control system reads the air temperature and transmits a signal to the compressor, causing it to turn on or off. Electronic sensors (thermistors) have a high resistance that varies with degrees Celsius. Mechanical thermostats operate on the principle of expansion of gas or liquid in a sealed flask. Ignorance of these nuances can lead to erroneous diagnosis.
Differences between mechanical and electronic controls
The search for a sensor directly depends on the type of control of your refrigerator. In models with mechanical thermostat everything is simpler: the temperature regulator, which you turn by hand, is often part of the control system. However, the sensitive element itself - the capillary tube - can go deep into the structure. In such units thermostat usually located inside the refrigeration chamber or on the external panel.
In devices with electronic control (No Frost) the situation is more complicated. There are no rotating knobs, and the temperature is set with buttons. The sensors here are small electronic components, often similar to small bullets or pills. They can be scattered in different areas: in the freezer, in the refrigerator compartment, in the freshness zone. Digital system requires accuracy, so there can be several sensors.
⚠️ Attention: Before any If you interfere with the electrical circuit of the refrigerator, be sure to disconnect it from the network. Working with 220V voltage without the appropriate skills and tools is deadly.
You can determine the type of your device by the presence of a display on the door. If the numbers change on the screen, it means there are electronic module thermistors inside. If you see a scale with numbers and an arrow, this is a classic mechanical regulator. This is the first thing you need to do before looking for where the cold sensor is located.
How to distinguish a working sensor from a burnt one?
The mechanical thermostat is called by the tester: when the temperature changes, the contacts should click and show circuit closure. An electronic sensor (thermistor) has a resistance that should change smoothly when heating or cooling. If the tester shows infinity or zero at any temperature, the element is faulty.
Location of the sensor in refrigerators with a drip system
In classic refrigerators with drop defrosting the sensor is most often integrated directly into the thermostat. If you have a model like Atlant, Biryusa or old Indesit, look for the regulator inside the camera. It is usually located at the top, right or left, sometimes hidden under a plastic cover. From it goes deep into the body a thin capillary tube.
This tube encircles evaporator or attached to its back wall. She is the one who “feels” the cold. In some models, the tube may be hidden behind the back wall of the chamber, which makes its replacement a complex procedure requiring thawing and partial disassembly. Thermoregulator in such cases acts as a control unit, and the tube acts as a sensitive probe.
If the refrigerator is old and mechanical, the sensor can be moved outside. There are models where the adjustment knob is located outside, above the door. In this case, the entire unit with the sensitive element is located in the technical compartment or behind the housing casing. Design of such units allows you to change the thermostat without complete defrosting, if the tube is not embedded in foam.
☑️ Diagnostics of a mechanical thermostat
Where to look for sensors in the system No Frost
System No Frost (without frost) assumes the presence of several sensors. Not only is the temperature controlled here, but the evaporator is also automatically defrosted. The main defrost sensor (defroster) is usually attached directly to the evaporator in the freezer. To get to it, you will have to remove the back panel of the freezer.
The refrigerator compartment of the No Frost system also has its own sensor. It is often hidden behind a plastic decorative panel on the back wall. In some models LG or Samsung it can be built into the air duct through which cold air comes from the freezer. Thermistor in such systems it is very compact and is connected via a connector to the main board.
Particular attention should be paid to the sensor defrosting the evaporator. He is responsible for ensuring that the heating element does not overheat the system. If it fails, the refrigerator may stop freezing or, conversely, start working without stopping. The location of this element is critical: it must touch the evaporator fins, but not be immersed in ice during normal operation.
⚠️ Attention: The plastic in modern refrigerators is very fragile in the cold. Do not attempt to remove the protective panels until the refrigerator is completely thawed and at room temperature, otherwise the latches may break.
Specific placement in two-chamber and multi-chamber models
In two-chamber units, one compressor is often used, but zone control may vary. In systems with one circuit the sensor is usually located in the refrigerator compartment, and the freezer is cooled according to the residual principle. If there are two circuits, then each chamber will have its own independent sensor. This complicates the search, as there are more elements.
Multi-chamber models, such as Side-by-Sidehave a whole network of sensors. There may be separate sensors for the freshness zone, drink bar, chest freezer. Electronic board interrogates them sequentially. The location is often non-standard: under shelves, behind decorative elements on the doors or in the basement of the refrigerator.
In models with a zone Zero Degree (zero zone), the temperature sensor is located directly in this compartment. It ensures that the temperature is maintained at around 0°C without freezing the food. The accuracy of this sensor is extremely important, so it is often calibrated at the factory and covered with a protective casing.
Table: Typical locations of sensors in different brands
Different manufacturers prefer their own layout schemes. Below is a table that will help you figure out where to look sensitive element in popular brands. Remember that within one series the location may vary depending on the year of manufacture.
| Brand | System type | Typical sensor location | Access features |
|---|---|---|---|
| Indesit | Drip / No Frost | Inside the chamber, under the light shade or on the back wall | Removal of the lampshade is often required |
| LG | No Frost | Behind the rear panel of the freezer (on the evaporator) | You need to unscrew a lot of screws, access is difficult |
| Samsung | No Frost / Digital Inverter | In the air duct between the chambers or in the freshness zone | The sensor is often paired with a fan |
| Atlant | Mechanics | Inside the refrigerator compartment, top right | Easy access, the capillary tube is visible |
| Bosch | No Frost | On the back wall of the refrigerator compartment | Hidden behind the decorative trim |
As seen from tables LG and Samsung often hide sensors deep inside the unit, which requires complete defrosting for 24 hours before repair. Mechanical models Atlant are more friendly to the home handyman. Always check the technical documentation of a specific model, as engineering solutions may change.
If you do not find the sensor in typical locations, check the area compressor. In some rare cases (usually in industrial or old household models), the thermostat can be placed in the engine compartment, although this is no longer typical for household refrigerators.
Fault symptoms and testing methods
Understand what temperature sensor out of order, it is possible by indirect signs. If the refrigerator works without interruption, turning the chamber into a freezer, or, conversely, remains silent until the food begins to deteriorate, this is an alarm bell. Also, a malfunction may be indicated by an error on the display (for example, a code F1, E1 or flashing indicators).
Required for accurate diagnosis multimeter. Remove the sensor and check its resistance. A working thermistor should have a resistance in a certain range (usually from 5 to 50 kOhm depending on the model) and change when heated with your fingers. A mechanical thermostat should “ring” (show zero) at room temperature and open the circuit in the cold.
- 🧊 Constant cold: The compressor does not turn off, a “fur coat” forms on the walls, food freezes - the sensor “does not see” the cold.
- 🔥 Lack of cold: The unit is silent, it’s warm inside - the sensor “thinks” that there is enough cold and does not give the command to start.
- ⚡ Short short circuit: If the sensor closes, the refrigerator may operate in emergency mode or constantly hum.
⚠️ Attention: Do not use open fire or boiling water to test the sensor. A sudden temperature change can destroy the sensitive element or plastic case, making it unusable even with working electronics.
Frequently asked questions (FAQ)
Is it possible to temporarily short-circuit the sensor to make the refrigerator work?
Technically, you can connect wires instead of the sensor, but this will lead to the refrigerator working will work continuously until you turn it off manually. This is dangerous due to overheating of the compressor and defrosting of food in the refrigerator compartment. Use this method only for a short-term test of the hypothesis.
Why does the refrigerator not turn on after replacing the sensor?
You may have installed a sensor with a different resistance value. Thermistors there are different ones (5 kOhm, 10 kOhm, 50 kOhm at 25°C). If the resistance does not match what the control board “expects” to see, the system will go into error and block the start of the compressor.
Where is the sensor located in the freezer?
In the No Frost system it is almost always attached to the evaporator (radiator), which is located behind the back wall freezers. In drip systems, there may not be a separate sensor in the freezer; there is one common thermostat for the entire volume or circuit.
How to understand which sensor has burned out if there are several of them?
Modern refrigerators with a display will tell you the error code themselves. By deciphering the code in the instructions (for example Er FF - freezer sensor error), you will understand which element requires replacement. Without a display, you will have to “ring” all the sensors in turn.