A failure in the operation of refrigeration equipment often takes you by surprise, especially when food inside begins to spoil or, conversely, vegetables begin to freeze. The first suspect in such situations usually becomes thermostat the device responsible for maintaining the set temperature. Understanding exactly where it is located is a key step before starting any repair or diagnostics.
In most household models, this component is hidden from the user's eyes so as not to disturb the aesthetics of the interior and protect delicate contacts from moisture. However, for a master or owner who decides to conduct an inspection, access to it is quite possible. It is important to understand that thermostat (or temperature sensor) can be mechanical or electronic, and the location of its installation directly depends on the type of control of your unit.
Before you start disassembling, you need completely de-energize device. Working with live electrical appliances is unacceptable and poses a direct threat to life. It is also worth preparing the necessary tool so that the search process does not turn into a long search for a screwdriver throughout the garage.
Types of thermostats and their effect on location
To successfully find a defective unit, you need to understand the principle of its operation. In old and budget models it is most often found mechanical thermostat. This device is a sealed capsule of gas or liquid that expands or contracts with changes in temperature. The capsule is connected to the control unit by a long bellows tube. It is this design feature that dictates where to look for the regulator itself.
In modern refrigerators with a system No Frost and electronic control, mechanics are replaced by thermal sensors (thermistors). These are small electronic components whose resistance changes depending on the ambient temperature. They do not have long tubes and are often built directly into the air channels or mounted on the walls of the evaporator.
⚠️ Attention: An attempt to replace an electronic sensor with a mechanical analogue (or vice versa) without altering the electrical circuit will lead to failure of the control board or compressor.
You can determine the type of your device by the presence of a rotary knob inside the camera. If the temperature is controlled by a knob with a scale from 1 to 7, you have classic mechanics. If there is a displayon the door, and the settings are made using buttons, then there is an electronic sensor installed inside.
Location in refrigerators with mechanical controls
In classic models such as Atlant, Biryusa or old Indesit, the thermostat is most often hidden inside the refrigerator compartment. This is logical, since the bellows must read the air temperature in this particular compartment. Usually it is located in one of the upper corners, next to the lampshade or directly combined with it.
To access it, you often need to remove the plastic casing that covers the light bulb. Under this plastic you will see a plastic box with wires and a tube coming out of it. In some models, for example, in a number of modifications Stinol, the thermostat can be hidden behind a decorative panel on the ceiling of the chamber, which needs to be carefully snapped off.
The bellows (that same long thin tube) goes deep into the wall or evaporator. It is through it that the thermal expansion of the working fluid is transmitted. When replacing, it is important not to damage this tube, since any microcrack will lead to gas leakage and incorrect operation of the device.
- 🔍 Look for the unit in the upper left or right corner of the refrigerator compartment.
- 🔍 Inspect the area around the lampshade - often the thermostat is attached nearby.
- 🔍 Check for removable decorative panels on the inner wall.
Sometimes manufacturers hide the regulator behind the back wall inside the chamber, but this is less common, as it complicates maintenance. In such cases, dismantling may require partial defrosting and removal of the internal lining.
Where to look for the sensor in No Frost models and with electronics
The situation with system refrigerators No Frost is radically different. There is no ice on the walls, and the air circulates through special channels. Electronic temperature sensors in such systems are located at several points for more precise control. One sensor monitors the temperature in the refrigerator compartment, another in the freezer, and the third can monitor the temperature of the evaporator to control the defrost system.
Most often, the main refrigerator compartment sensor in such models is hidden in air duct. This is a plastic channel located on the back wall or top of the camera. To get to it, you will have to remove the plastic panel on the back wall. The sensor is a small plastic cylinder or “bullet” on a wire that is inserted into a special socket.
In the freezer compartment of No Frost systems, the sensor is often mounted on the evaporator or mounted in the wall next to the fan. In models with a “zero temperature” or “Fresh Zone” zone, additional sensors can be installed directly in this compartment to maintain accurate 0...+2 °C.
Why are there several sensors?
In electronically controlled systems, the microprocessor compares readings from different points. If the evaporator sensor shows -10°C, and the chamber still has +5°C, the system will understand that the air duct is clogged or the fan is faulty and will generate an error.
It is important to note that in some premium brand models Liebherr or Bosch sensors can be integrated into a multilayer wall structure and not have quick access without serious disassembly of the case.
Specific placement in two-chamber and single-chamber models
The design of the refrigerator dictates the logic of the placement of control elements. In single-chamber models (where the freezer is just a shelf at the top), there is always one thermostat, and it controls the overall temperature. Its location is standard - inside the main chamber under the top cover.
In two-chamber units with one compressor, the thermostat is usually located in the refrigerator compartment. It turns off the compressor when it gets cold enough in the “plus” chamber. At this time, the freezer freezes food “according to the residual principle.” Therefore, if your lower chamber is not freezing, but the upper chamber is working normally, the problem may not be in the thermostat, but in a freon leak or a clogged capillary.
In models with two compressors (a separate circuit for the refrigerator and a separate one for the freezer), there are two thermostats. They are completely independent. In this case troubleshooting narrows down to a specific compartment that has stopped cooling.
| Type of refrigerator | Number of thermostats | Typical location | Access |
|---|---|---|---|
| Single-chamber | 1 | Inside the chamber, near the ceiling | Medium (remove the ceiling) |
| Two-chamber (1 compressor) | 1 | Refrigeration compartment | Medium/Complex |
| Two-chamber (2 compressors) | 2 | In each compartment separately | Different |
| No Frost (Electronic) | 2-3 | Air ducts, evaporator | Complex (disassembly) |
It is worth remembering that in some old Soviet refrigerators (Minsk, Saratov) the thermostat could be located outside, on the top panel of the case, but Such models are extremely rare today and are more likely to be of museum value.
Signs of a malfunctioning thermostat
How do you understand that the problem lies in this particular unit, and not in the compressor or freon? There are several obvious symptoms that indicate failure thermostat. The first and most important sign is that the refrigerator does not turn off at all. The compressor hums continuously, trying to catch up with the temperature, which, according to the readings of the “broken” sensor, has still not been reached.
The second scenario is that the refrigerator does not turn on at all. The contacts inside the thermostat have oxidized or are stuck open. In this case, it becomes warm inside, the light is on, but there is no cold. Sometimes the “resuscitation” method helps: if you knock on the regulator handle, the contacts can close and the unit will start, but this is only a temporary solution.
⚠️ Attention: If the refrigerator turns on and off at too short intervals (picket fence), this may also indicate incorrect calibration or sticking of the thermostat contacts.
The third sign is incorrect temperature. Food in the refrigerator compartment freezes, although the knob is turned to minimum, or, conversely, it is warm in the chamber, although it is turned to maximum. This indicates that the bellows lost tightness or the calibration spring has shifted.
Replacement instructions: step-by-step algorithm
If the diagnostics confirm the malfunction, replacement is necessary. This process requires care, especially when working with mechanical models where the bellows tube can be damaged. First, we remove the old part, remembering or photographing the order in which the wires are connected.
Next, you need to install a new thermostat. It is important that the model matches the fit dimensions and length of the capillary tube. If the tube of the new regulator is longer, you can carefully twist it into a ring, but under no circumstances bend or cut it. You cannot extend a short tube - you will have to look for another model.
After installation, you need to check the operation of the system. We turn on the refrigerator and wait for the cycle. If the compressor turns off when the desired temperature is reached, the repair was successful.
☑️ Checklist before replacement
Do not forget to adjust the temperature after replacement. For mechanical models, this is done by trial and error by turning the knob. For electronic ones, you may need to enter the service menu or calibration through control panel.
Common mistakes during self-repair
The most common mistake is ignoring safety precautions. Trying to replace a thermostat while it is live may result in an electric shock. Always unplug the plug from the socket before starting work.
The second mistake is the use of force when dismantling plastic elements. Plastic becomes brittle in the cold. If the panel cannot be removed, check that all the screws are removed and that you have not forgotten to remove any shelves or drawers that may be blocking it.
The third mistake is installing the “wrong” thermostat. They differ in on/off temperature and tube length. Installing an unsuitable component will result in the refrigerator operating abnormally, which will shorten the service life of the compressor.
If you doubt your abilities or cannot find a thermostat in your model, it is better to turn to professionals. Incorrect installation can lead to more expensive repairs.
Can an old thermostat be repaired?
Theoretically, a mechanical thermostat can be disassembled, the contacts cleaned and the spring bent. However, this requires high qualifications and special equipment for calibration. In practice, it is easier and more reliable to buy a new unit, which is inexpensive, than to risk food and time.
Why does the refrigerator not turn off after replacing the thermostat?
You may have installed a thermostat with other temperature parameters (for example, for a freezer instead of a refrigerator). Also, the reason may be a freon leak: the compressor works constantly, trying to reach a temperature that it cannot reach due to a lack of refrigerant.
Where is the thermostat in the Indesit refrigerator?
In most Indesit models with mechanical control, the thermostat is located inside the refrigerator compartment in the upper left corner, hidden under a plastic casing along with the lighting lamp. In some models, access is through the rear wall from the outside.
How to check the thermostat with a multimeter?
You need to remove the thermostat, put the multimeter in dial mode and apply the probes to the contacts. At room temperature the circuit should ring (if it is a normally closed contact). If you put the sensor in the freezer for 15 minutes, the circuit should break (stop ringing).