If your Samsung stopped supporting the set mode or started freezing food, the first thing that comes to mind is a problem with thermoregulation. Temperature sensor is a key element of the control system responsible for reading readings inside the chambers. It is this that signals the control unit to turn the compressor on or off.
In modern models of the Korean brand, these elements are often called thermistors, and their location depends on the specific series of the refrigerator. Fault finding can take from 15 minutes to an hour if you know where exactly to look. In this article we will analyze in detail the geometry of the internal space of different models.
Understanding that where is the temperature sensor of a Samsung refrigeratorwill allow you to independently carry out initial diagnostics or replace a failed element. This knowledge will save time on calling a technician if the problem can be solved by simply replacing the part.
The principle of operation and types of sensors in the No Frost system
Modern units Samsung with the system No Frost use electronic control, which is based on the readings of several sensors. Unlike old mechanical thermostats, modern thermistors change their resistance depending on the ambient temperature. The control unit reads these changes and makes decisions about the operation of the compressor and fans.
Usually, the design has several control points: one monitors the air temperature in the refrigerator compartment, the other in the freezer, and the third controls the evaporator defrost process. Failure of any of them leads to incorrect operation of the entire system. For example, if the defrost sensor is broken, the refrigerator may stop defrosting the evaporator, which will lead to ice buildup.
It is important to understand that electronic sensors are more sensitive to changes in voltage and humidity than their mechanical predecessors. They are small elements, often enclosed in a plastic case or filled with sealant, with two suitable wires.
Where to look for the sensor in the refrigeration room chamber
In most models Samsung the sensor that controls the temperature in the main compartment is located in the upper part of the chamber. However, its exact location depends on the design of the internal plastic and the year of manufacture of the device. Most often, it is hidden from the user’s eyes to protect it from mechanical damage.
The first place to look is ceiling panel or the decorative air duct grille. In some series, such as RB30 or RB37, the sensor may be hidden behind a plastic cover that must be carefully removed. Sometimes it is fixed directly to the wall of the air duct, through which cold air flows from top to bottom.
The second location option is the side wall in the upper third of the chamber. Here the element can be built into the plastic structure itself or hang on a wire if the previous owners have already carried out repairs. Wiring usually goes deep into the wall to the main control board.
- 🔍 Look for a round hole with a diameter of 5-8 mm in the ceiling or rear plastic walls.
- 🧊 Check the area near the light bulb, as sensors are often grouped there.
- 🌬️ Inspect the outlets of the air ducts where cold air is blowing.
If you do not see an obvious element, it may be integrated into the air flow control unit (Air Control). In such cases, access to it will require partial disassembly of the internal plastic.
Location of the thermistor in the freezer compartment
In the freezer compartment the situation is slightly different due to low temperatures and the defrost system. Here temperature sensor often combined or located in close proximity to the defrost heater. This is logical, since the control unit needs to know exactly when to heat up so as not to melt the plastic parts.
Most often the element is located behind rear panel the freezer. To get to it, you will have to remove all the shelves and drawers, and then unscrew the screws holding the plastic wall. Behind it lies the evaporator and defrost system. The sensor can be attached to the fins of the evaporator or inserted into a special socket on the tube.
In models with a bottom freezer, access is through the freezer door. In Side-by-Side models, the sensor may be located in the side wall or in the air circulation channel between the chambers. Access to it in such cases, it may be limited by design features.
⚠️ Attention: Before removing the back panel in the freezer, be sure to unplug the refrigerator for at least 2 hours. This is necessary for the compressor to cool down and the pressure in the system to stabilize, as well as to avoid electric shock.
Visually in the freezer it looks like a small black or white “mushroom” on a wire, or like an element soldered into an aluminum tube. Insulation integrity wires in this place is critically important, since water forms there during defrosting.
☑️ Finding the sensor in the freezer
Evaporator defrost system sensors
Sensors that are solely responsible for the defrosting cycle deserve special attention. In refrigerators Samsung there may be one or two of them. One controls the beginning of defrosting (freezing of ice), the other controls the end (complete thawing). They are located directly on the evaporator.
They can only be found after removing the back panel in the freezer compartment. They are attached to the aluminum fins of the heat exchanger or inserted into special holes in the evaporator tubes. Often they look like capsules filled with resin, or small cylinders.
The malfunction of these elements leads to the fact that the refrigerator either does not defrost at all (the “fur coat” freezes up), or heats up for too long, increasing the temperature in the chamber. Diagnostics these sensors require testing with a multimeter, as it is possible to visually determine their performance difficult.
Symptoms of defrost sensor failure
The refrigerator hums, but does not cool; Ice forms on the back wall of the refrigerator compartment; a large lump of snow freezes in the freezer; the display shows error 21E or 22E.
Table of error codes and corresponding sensors
Modern refrigerators Samsung are equipped with a self-diagnosis system. When the thermistor fails, a combination of numbers and letters lights up on the display. Understanding these codes will help you quickly identify which one temperature sensor needs replacement.
| Error code | Problem description | Probable location | Nature of the malfunction |
|---|---|---|---|
| 21E / 21C | Error in the refrigerator compartment sensor | Upper part, under the ceiling | Open circuit or short circuit |
| 22E / 22C | Error in the freezer compartment sensor | Behind the rear panel of the freezer | Resistance mismatch |
| 23E / 23C | Defrost sensor error | On the evaporator (in the freezer) | Open or short circuit |
| 24E / 24C | Flex Zone sensor error (if any) | In a variable climate zone | Signal failure |
The presence of the letter "C" at the end of the code usually indicates a short short circuit (Close), and "E" - for open circuit or error (Error). However, in different models Samsung the designations may vary slightly, so always check the technical documentation.
Instructions for checking and replacing the thermistor
If you have determined which element has failed, it must be replaced. To do this you will need multimetera screwdriver and possibly a soldering iron. The process begins by turning off the power and removing the panels to access the sensor.
First you need to disconnect the sensor connector from the wiring harness. Then check the resistance using a multimeter. At room temperature, a working thermistor Samsung usually shows a resistance of about 5-10 kOhm (the exact value depends on the model). When the hands heat up, the resistance should drop.
If the device readings do not change or the resistance is zero/infinity, the part is faulty. The new sensor is installed in place of the old one. It is important to ensure tightness of the connectionif the wires have to be twisted or soldered, so that moisture does not get inside.
⚠️ Attention: Never use sensors from other brands or with a different resistance rating. This will lead to incorrect operation of the compressor and possible failure. Use only original spare parts or high-quality analogues with identical characteristics.
Frequent questions and problems when searching
Users often encounter difficulties when making repairs themselves. One of the main problems is the lack of an obvious hole for the sensor. In such cases, it can be built into a common board or hidden under a layer of mounting foam, which complicates access to the part. Another issue concerns compatibility. Sensors from different series access to part.
Another issue concerns compatibility. Sensors from different series Samsung may differ in wire length or connector shape. Before buying a new part, it is better to remove the old one and compare them visually, and also measure the resistance.
Sometimes after replacing the sensor, the error on the display does not disappear immediately. In this case, it is necessary to completely de-energize the refrigerator for 10-15 minutes to reset errors in the memory of the control unit. After switching on, the system will conduct self-diagnosis and, if the malfunction has been eliminated, the error will disappear.
Is it possible to temporarily operate a refrigerator without a sensor?
Theoretically, it is possible if you close the circuit or install a resistor with a certain resistance, simulating normal temperature. However, this will lead to the refrigerator operating in emergency mode, either constantly freezing or not turning off. This is a temporary solution only until a technician arrives or a spare part is purchased.
Why does the new sensor not work?
There may be several reasons: the resistance (nominal) is incorrectly selected, poor contact in the connector, a wire break in the harness or a malfunction of the control board itself, which cannot correctly read the readings of a working sensor.
Where to buy an original sensor for Samsung?
It is better to order original spare parts from authorized service centers or specialized stores of spare parts for household appliances, indicating the exact model of the refrigerator (serial number).