Finding the place where thermostatbecomes a priority task when the refrigerator stops turning off or, conversely, stops freezing. It is this small device that is responsible for maintaining a given temperature regime, opening and closing the electrical circuit of the compressor at the right time. Understanding its location is necessary not only for replacing a failed part, but also for competent diagnosis of faults, which are often confused with a breakdown of the compressor itself.
The design of modern and old refrigeration units differs significantly, therefore the installation locations of temperature sensors can be completely different. In some models, the thermostat is hidden under a plastic panel inside the chamber, in others it is placed outside, and in the most modern systems its role is played by complex electronic sensors. To find the element, you will have to arm yourself with a tool and basic knowledge about the structure of your model Indesit, Atlant or any other.
In this article we will analyze in detail the layout of thermostats, methods for checking them and the nuances of replacement. It is important to know that in refrigerators with a No Frost system there may be several thermostats: one to control the compressor, and the other (defrost) for the defrosting system. Careless interference with the operation of the system can lead to leakage or damage to the wiring, so follow the instructions carefully.
The principle of operation and types of thermostats
Before looking for where the regulator is hidden, you need to understand how it functions. Classic mechanical thermostat is a sealed system filled with gas or freon, which responds to changes in evaporator temperature. When cooling, the gas is compressed and the membrane opens the contacts, stopping the compressor. When the temperature rises, the gas expands and the circuit is closed again.
Electronic thermostats work differently: they use thermistors, the resistance of which changes depending on the temperature. Such elements are often located on control boards or in hard-to-reach places, since they do not require direct communication with the evaporator through a capillary tube. Unlike mechanics, they cannot be checked by “continuity” without special equipment.
Most household refrigerators use the following types of regulators:
- 🔹 Mechanical with a bellows and capillary tube - most common in older models and budget series.
- 🔹 Electronic temperature sensors (thermistors) - installed in electronically controlled systems.
- 🔹 Combined systems - where a mechanical thermostat controls the compressor, and a separate sensor monitors defrosting.
⚠️ Attention: The capillary tube of a mechanical thermostat is very thin and easily damaged. If you carelessly remove the sensor from the evaporator, you can break the tightness of the system, which will require an expensive refill with freon.
How to distinguish mechanics from electronics?
A mechanical thermostat always has an adjustment knob inside the chamber (or a rod under it) and an outgoing tube into the wall. An electronic sensor is a small wire with a connector that goes deep into the plastic or is attached to the evaporator, without a handle visible to the user.
Location in single-chamber refrigerators
In classic single-chamber models, such as old ZIL or Biryusa, the thermostat is easier to find everything. It is almost always located inside the refrigerator compartment. Most often, it is hidden behind a plastic cover on which the temperature control knob is attached. To get to it, you need to carefully remove this handle (often it is simply pulled together with force) and unscrew the screws that secure the decorative panel.
Under the panel you will see the thermostat housing itself with the wires suitable for it and a capillary going into the chamber wall or into the evaporator tube. In some modifications, the housing can be mounted directly on the chamber wall or on the evaporator. You can get to it by removing the back cover inside the camera or dismantling the lighting lamp, if it is located nearby.
The main mounting points in single-chamber models:
- 🔹 Behind the temperature control knob on the ceiling or side wall.
- 🔹 In the niche above the door (in top of the camera).
- 🔹 Near the lampshade.
When dismantling, be careful with the wiring. Often the wires are inserted into the grooves of the plastic, and a sharp tug can lead to their breakage. If you are planning a replacement, take a photo of the wire connection diagram before disconnecting them, since the color markings may differ from one manufacturer to another.
Where to look in two-chamber models
In two-chamber refrigerators, the situation becomes more complicated. The thermostat can be located either in the refrigerator compartment or in the freezer compartment, depending on which circuit it controls. In models with one compressor, the thermostat is most often located in the fridge compartment, since this is where the main operating mode is set.
If the adjustment knob is located inside the fridge compartment, then the device itself is hidden behind it. However, in models with a system No Frost or in units with remote control, the thermostat can be located outside the chambers - in a special box at the top of the refrigerator or even at the back, near the compressor. In such cases, the capillary tube passes through the entire height of the case.
To search, follow these steps:
- Inspect the insides of the refrigerator compartment for the presence of plastic plugs or panels.
- Check the top of the refrigerator (above the upper chamber) - a technical compartment is often hidden there.
- If access from the inside is not possible, you may need to remove the top cover of the refrigerator case.
Specifics of Atlant, Indesit and Bosch refrigerators
Different manufacturers have their own preferences in the layout of components. For example, in refrigerators Atlant the thermostat is most often located in the upper right corner of the refrigerator compartment. To get to it, you need to remove the plastic cover covering the lampshade. The thermostat is mounted on a bracket, and its capillary tube is inserted into a channel inside the rear wall.
In models Indesit i Ariston the thermostat is often located inside a plastic box, which is attached to the ceiling of the chamber. A characteristic feature is the presence of a long corrugated tube that leads to the evaporator. In some series Bosch the thermostat can be combined with a defrost sensor and located directly on the evaporator, which requires partial defrosting and removal of the rear panel for access.
Comparative table of location in popular models:
| Brand | Typical location | Access | Features |
|---|---|---|---|
| Atlant | Upper right corner | Through the lamp shade | Mounting on a bracket |
| Indesit | Camera ceiling | Removing the plastic box | Long capillary tube |
| Bosch | Behind the rear panel | Complex (disassembly) | Often combined with the No Frost system |
| Liebherr | Side or top | Removing the decorative panel | High calibration accuracy |
When working with imported models, it is important to consider that their design may be more dense. Dismantling requires care with plastic latches, which become fragile in the cold.
Diagnostics of thermostat malfunctions
Having understood where the thermostat is located, you need to check its functionality. The easiest and most reliable way to check a mechanical thermostat is to use a multimeter in dial mode. To do this, you need to disconnect the wires from the contacts of the device and short-circuit the probes to its terminals.
If at room temperature the multimeter shows “0” (the circuit is closed), and when the sensor is placed in the freezer (or when the case is cooled with alcohol) the circuit opens, the device is working. If the circuit does not close at all or does not open in the cold, the thermostat is subject to replacement. Also, a sign of a malfunction may be the absence of a characteristic click when turning the knob.
Symptoms of thermostat failure:
- 🔹 The refrigerator works without interruptions, the temperature drops too low.
- 🔹 The compressor does not turn on at all, although the light is on.
- 🔹 Snow is melting in the refrigerator compartment, and food is defrosting in the freezer.
- 🔹 The temperature regulator scrolls endlessly or is jammed.
⚠️ Attention: Before checking with a multimeter, be sure to disconnect the refrigerator from networks! Working with live electrical wiring is life-threatening and can damage the control electronics.
The process of replacing a thermostat
Replacing a thermostat is a procedure accessible to a home craftsman, but requires care. Once you have determined the location where the device is located and are convinced that it is faulty, you need to purchase a similar model. The part number is usually located on the body of the old thermostat.
The replacement process involves turning off the power, removing the protective panels, disconnecting the wires (after photographing them) and carefully removing the capillary tube from the channel. The new thermostat is installed in the reverse order. Pay special attention to fixing the tube - it must be inserted to the same depth as the old one, otherwise the temperature regime will be disrupted.
☑️ Algorithm for replacing the thermostat
After assembly, you need to turn on the refrigerator and check its operation for several hours. If the compressor begins to turn off and turn on normally, and the temperature has stabilized, the repair was successful.
Common mistakes during self-repair
When searching for and replacing a thermostat, beginners often make mistakes that lead to repeated breakdowns. One of the most common is damage to the capillary tube when trying to pull it out of the canal. If the tube is pinched or burst, the freon from the thermostat system will evaporate, and it will stop working, even if it is electrically working.
Another error is incorrect installation of the analogue. Thermostats may differ in the length of the capillary tube, on/off temperature and mounting method. Installing a “similar” thermostat without taking these parameters into account may result in the refrigerator freezing too weakly or, conversely, turning the chamber into a glacier.
Do not forget that in modern electronically controlled models, replacing a mechanical thermostat with an electronic one (and vice versa) is impossible without reworking the entire control system. Always check the compatibility of parts using the catalog number.
Is it possible to temporarily remove the thermostat to make the refrigerator work?
Theoretically, if you close the thermostat contacts directly, the compressor will start and run continuously. However, this is an emergency measure and may result in food in the refrigerator compartment defrosting and compressor failure due to lack of rest cycles. This method can only be used for short-term freezing of food with a faulty thermostat.
Why does the new thermostat click, but the refrigerator does not turn on?
If you hear clicks, but the compressor is silent, the problem may not be in the thermostat, but in the start relay, the compressor itself, or the wiring. It is also possible that the new thermostat is faulty or incorrectly connected (no contact in the circuit).
Is it necessary to defrost the refrigerator before replacing the thermostat?
Full defrosting is not necessary if access to the thermostat is in the upper part of the chamber. However, if access to the evaporator or rear wall is required, defrosting is necessary for safety and ease of operation. Ice can interfere with accurate installation of wires.