When the refrigerator stops maintaining the set temperature or, conversely, begins to turn food into ice blocks, the first thought is often to call a technician. However, in many cases, the problem lies in a banal malfunction thermostat, which can be replaced independently if you have basic skills. Understanding where exactly this unit is located is a key diagnostic step, since the design of equipment from different manufacturers can differ significantly.
The thermostat, or thermostat, is the “brain center” of the cooling system, which reads the temperature inside the chamber and sends a command to the compressor to turn on or off. If this sensor fails, the refrigerator operates in chaotic mode. In this article we will analyze in detail how to find this element in various models, what tools will be needed to access it and what to pay special attention to so as not to aggravate the situation.
Before starting disassembly, you must disconnect the appliance from the power supply. This a mandatory safety conditioncannot be ignored, since the work will be carried out in close proximity to electrical contacts and metal structural elements. Next, you should empty the refrigerator compartment of food and shelves to ensure free access to the internal walls.
Design features of location in different types of refrigerators
The search for a thermostat directly depends on the defrosting system of your unit. In older models with manual defrosting or drip system thermostat most often it is located inside the refrigerator compartment. It can be found in one of the top corners, often hidden behind a plastic trim or built into the lighting control unit. In such devices, the capillary tube of the sensor goes deep into the wall or is attached to the evaporator.
Modern models with the system No Frost have a more complex architecture. Here the thermostat can be located both inside the chamber (often behind the back panel) and outside - in a niche above the door or in the lower part of the housing, next to the compressor. In some cases, the air temperature sensor is hidden deep in the air duct, and access to it requires partial disassembly of the internal space.
In two-compressor models, the situation is complicated by the fact that thermostats (or their electronic analogues) can be installed for each chamber separately. In such cases, it is important not to confuse the refrigerator compartment sensor with the freezer compartment sensor, since their calibration and capillary length may differ. Careful study of the technical documentation or diagram of a specific device greatly simplifies navigation through the insides of the unit.
It is worth noting that in inverter models, the mechanical thermostat is often replaced by an electronic sensor, which looks like a small “tablet” or cylinder on a wire. The location of such elements is less standardized and may vary from manufacturer to manufacturer, requiring an individual approach to the search.
Detailed instructions: how to find a thermostat in single-chamber models
If you are the owner of a classic single-chamber refrigerator (for example, old models Atlant, Biryusa or Indesit), then you should start searching from the inside of the refrigerator compartment. Usually the thermostat is hidden under a plastic cover, which can also serve as a lampshade for a lighting lamp. To get to the unit, you need to carefully remove this cover by unscrewing the fixing screws or unlatching the latches.
After dismantling the cover, you will see a metal or plastic box with wires coming out of it - this is the one you are looking for thermostat. A long corrugated tube (capillary) extends from it, the end of which is fixed to the evaporator or inserted into a special socket in the chamber wall. It is this capillary that reacts to changes in temperature, transmitting a signal to the contacts inside the regulator body.
In some modifications, the thermostat can be mounted not in a corner, but on the ceiling of the chamber, or even displayed on an external control panel, if we are talking about more modern versions with mechanical knobs on the front. In the latter case, the temperature control knob is directly connected to the thermostat shaft, which is located behind the front wall of the case.
- 🔍 Carefully inspect the area around the light bulb - in 80% of old models the thermostat is hidden there.
- 🔧 To remove the cover, you may need a flat screwdriver, act carefully so as not to break the plastic latches.
- ❄️ Do not pull hard on the capillary tube, it is very thin and is easily damaged, which will lead to freon leakage from the sensor.
- 📸 Before disconnecting the wires, take a photo of the connection diagram so that you do not confuse the contacts during assembly.
⚠️ Attention: In models with a “crying” evaporator, the thermostat capillary is often frozen to the surface of the evaporator. If you remove it carelessly, you can damage the aluminum tubes of the evaporator, which will require expensive soldering and refilling of the refrigerator.
If the thermostat is not visually found in the usual places, it is worth checking the technical data sheet of the device. The exact layout of the nodes may be indicated there. It is also useful to know that in some cases the thermostat can be combined with a defrost sensor, which is typical for transitional models of equipment.
Searching for a sensor in No Frost system refrigerators
In units equipped with the system No Frost, finding a thermostat becomes a more complex task. There is no exposed weeping evaporator inside the chamber, as it is hidden behind the rear plastic panel. The thermostat in such models is often located in a special compartment, which can be accessed after removing this panel. However, in order to remove the panel, you often have to dismantle all the shelves, drawers and even the door.
In some cases, especially in models LG or Samsung, the thermostat (or defrost sensor, which is often confused with the main thermostat) is located in the evaporator area, deep in the “bowels” of the freezer or refrigeration chamber. To access it, you may need to bend back the insulation or remove additional metal screens. It is important not to confuse the main thermostat, which controls the air temperature, with defrost sensorwhich monitors the heating of the heating element.
Sometimes manufacturers place the control unit and thermostat in the upper part of the refrigerator, above the door. In this case, you will need to remove the decorative cover on top of the case. This solution is typical for embedded technology and some models Bosch or Siemens. In such designs, the capillary tube can be replaced by an electrical wire going to the sensor inside the chamber.
Particular attention should be paid to models with a freshness zone. They can have two thermostats installed: one for the main chamber, the other for the zero compartment. The search for the second sensor usually leads to the bottom of the refrigerator compartment or to a separate drawer.
What is the difference between a No Frost thermostat and a regular one?
The main difference is in the design and installation location. In No Frost, the thermostat is often paired with a defrost timer and sensors that monitor the defrosting process of the evaporator. A conventional mechanical thermostat simply closes the compressor circuit when the temperature rises. In No Frost systems, the operating logic is more complex, and replacing a conventional thermostat with a specialized one (or vice versa) is impossible without altering the control system.
Location in two-chamber and multi-chamber refrigerators
Two-chamber refrigerators can have either one or two compressors. If there is only one compressor, then the thermostat is usually located in the refrigerator compartment, and only a capillary or damper goes from it to the freezer. If there are two compressors, then there are also two thermostats - one for each chamber. In this case, you need to search for them independently of each other, following the logic for single-chamber models.
In modern multi-chamber systems (for example, Side-by-Side), mechanical thermostats are rare. Their place is taken by electronic sensors scattered throughout the volume: in the air ducts, in the evaporator area, in containers for vegetables. They can only be found by looking at the wiring harnesses going to the main control board. Typically, such sensors look like small black or white cylinders at the end of a wire.
When searching for two-chamber models, it is important to understand the principle of cold circulation. If the cold is pumped from below (into the freezer), then the main temperature sensor may be located there, and the cold enters the upper compartment through the channels. In such cases (often found in Indesit i Stinol) the thermostat is hidden in the freezer, often behind a panel or at the top of a niche.
☑️ Algorithm for finding a thermostat
Table: Typical location of thermostat by brand
To systematize the information, we provide data on the most common locations for installing thermostats in popular brands. Remember that there may be different series within one brand, so the data is for reference only.
| Brand | Typical location | Access features |
|---|---|---|
| Atlant | Inside the chamber, left or right at the top | The plastic cover with the lamp is removed |
| Indesit | In the freezer (top) or in the refrigerator | Often requires removing the top panel of the freezer |
| LG | Behind the back wall (No Frost) or in the corner cameras | Requires complete defrosting and removal of the panel |
| Bosch | In a niche above the door or inside the chamber | Access through the top cover of the case |
| Samsung | Behind the rear panel or in the control unit | Complicated disassembly, a lot of latches |
The table shows that Atlant and Indesit more often use the classic layout, available for quick repairs. Brands like LG i Samsung hide the nodes deeper, which requires more time for diagnosis. Always check with a specific model, as engineering solutions change from year to year.
Symptoms of malfunction and the need for replacement
How to understand that the thermostat has really failed, and not a problem in the compressor or freon leak? There are a number of characteristic symptoms. Firstly, the refrigerator can work non-stop, without turning off for days, which leads to the formation of a thick crust of ice and excessive energy consumption. Secondly, the unit may not turn on at all, silently “standing” with defrosted food.
The third sign is incorrect operation: the refrigerator turns on too often or, conversely, rarely, without reaching the desired temperature. If you turn the regulator knob, but the nature of the motor does not change, this is a sure sign of breakdown thermostat. Also, a malfunction may be indicated by a sharp click, after which the refrigerator goes silent or, conversely, starts.
It is important to distinguish a breakdown of the thermostat from a malfunction of the start relay or compressor. If you hear a click when you turn it on, the motor hums for 1-2 seconds and turns off - the problem is most likely in the compressor or relay. If there is complete silence or the motor runs non-stop, suspicion falls on the thermostat.
⚠️ Attention: If your refrigerator is equipped with electronic control (display on the outside), then there may not be a mechanical thermostat at all. In such cases, the electronic control module and temperature sensors (thermistors) are responsible for the temperature, which are checked by resistance, and not by contact closure.
Nuances of self-replacement and precautions
Replacing a thermostat is not a complicated procedure, but requires care. The main rule: the new thermostat must be a complete analogue of the old one. They differ in the length of the capillary tube, response temperature range and type of contacts. Installing an unsuitable model will lead to incorrect operation: either the food will spoil or ice will freeze.
When installing a new sensor, it is necessary to repeat the path of laying the capillary tube as accurately as possible. It must not be bent at an acute angle, twisted or pulled. The end of the tube should be in tight contact with the evaporator (often it is fixed with a special clamp or inserted into a hole). Poor contact will lead to a delayed response of the thermostat.
After installing and connecting the wires (do not forget about grounding, if any!), do not rush to load the products. Turn on the empty refrigerator and monitor its operation for several hours. It should reach temperature and turn off. If the cycle proceeds normally, the repair can be considered successful.
Repairing a refrigerator with your own hands is a budget-saving and useful experience. However, if you feel unsure of your abilities or the design of your unit requires complex disassembly with a violation of the tightness of the circuit, it is better to turn to professionals. Take care of your equipment, and it will last for many years.
Is it possible to replace the thermostat with an analogue with a different marking?
Only if their parameters (temperature range, capillary length, type of contacts) completely coincide. Visual similarity does not guarantee compatibility. It is better to look for an exact analogue by catalog number.
Why does the refrigerator not turn off after replacing the thermostat?
Possible reasons: the capillary is installed incorrectly (no contact with the evaporator), a defective new thermostat, a freon leak or a compressor malfunction. Also check the tightness of the door closure.
Where is the thermostat located if the adjustment knob is on the ceiling?
In such models, the thermostat itself is usually located behind a decorative panel on the ceiling of the chamber or in the space above the refrigerator compartment, and the handle only transmits rotation to its shaft through a plastic rod.
How check the thermostat without a multimeter?
You can make a temporary jumper between the contacts of the wires going to the thermostat. If the refrigerator starts working after being plugged in, the problem is in the thermostat. But this method requires caution and understanding of electrical circuits.