Two-chamber refrigerators of the brand Indesit are deservedly popular due to their reliability and simplicity of design. However, even the most proven equipment requires repair over time, and one of the most common causes of failure is thermostat. It is this unit that is responsible for maintaining the set temperature inside the chambers, starting and stopping the compressor as needed. When the refrigerator stops turning off or, conversely, stops freezing, the first thing the technician looks at is the temperature sensor.
Users are often lost trying to find the answer to the question of where exactly this important element is located in their model. The location may vary significantly depending on the year of manufacture of the device and the type of defrosting system. In some cases, access to it opens immediately after removing the lampshade; in others, complete disassembly of the rear wall is required. Understanding the general diagram of the device will help you save time and not damage unnecessary parts during diagnostics.
In this article we will analyze in detail all possible options for the location of the thermostat, provide visual references and explain how to safely get to the unit. We will consider models with a drip system and No Frost, since design differences play a key role here.
The principle of operation and the role of the thermostat in the cooling system
The thermostat, or thermostat, is a mechanical or electronic device that continuously reads the temperature inside the refrigerator or freezer. In classic models Indesit most often, mechanical sensors with a bellows tube are used. Capillary tube such a thermostat is mounted on the evaporator and responds to changes in the refrigerant pressure inside itself, closing or opening the electrical circuit of the compressor.
Electronic systems, which are found in more modern lines, operate on the basis of thermistors. These semiconductor elements change their resistance depending on the ambient temperature. The signal is transmitted to the electronic control module, which already makes the decision to turn on the motor. The difference in operating principle directly affects where the sensor is physically located: the mechanics need to be attached directly to the cooling element, and the electronics can be placed in any convenient place inside the chamber.
⚠️ Attention: Mechanical thermostats are extremely sensitive to physical damage. If you accidentally bend or puncture the capillary tube during installation, the refrigerant inside will evaporate and the unit will have to be completely replaced. Work with utmost care.
Understanding what type of sensor is installed in your refrigerator is critical to your search. If you hear a characteristic click when you turn the temperature control knob, then you have a mechanical system. In this case, you need to look for the place where the tube enters the camera body. If the control is digital, then the sensor is most likely hidden behind plastic panels.
Location of the thermostat in the refrigerator compartment (Drip system)
In most two-chamber refrigerators Indesit with a drip defrost system, the thermostat is located directly in the refrigerator department. The traditional installation location is the area above the top shelf or in the corner, closer to the lampshade. The design often involves bellows tube passing through the back wall and contacting the evaporator hidden behind the plastic.
To gain access to the mechanical unit, it is usually sufficient to remove the plastic casing hiding the light bulb. In some models, for example, series Indesit SBS, the thermostat can be hidden behind a decorative trim in the upper right or left corner. Fastening elements often hidden under plastic plugs that need to be carefully pryed off with a flat screwdriver. Do not use excessive force, as the plastic on old refrigerators becomes brittle.
If the temperature control knob is located on the outer panel of the door or is located inside the chamber in a visible place, then the mechanism itself is located immediately behind it. In models where the handle is located outside on top, the thermostat is attached to the inner wall of the refrigerator in the projection of this handle. You will need to remove the top cover of the refrigerator (if it is removable) or dismantle the internal plastic panel to see contact group and suitable wires.
Visually, the thermostat in such models is a metal box with a long copper tube coming out of it. This tube runs along the back wall and is attached to the evaporator with special clamps. It is this area that most often requires inspection when replacing. It is important not to confuse the thermostat tube with the tubes of the defrost circuit or condensate drainage.
Searching for a temperature sensor in the No Frost system
The situation with refrigerators Indesitequipped with the system No Frostis radically different. Here you will not find the usual twister with a tube going deep into the main chamber. Such units use electronic sensors (thermistors) that are mounted directly into the evaporator unit or air ducts. Access to them is blocked by several layers of plastic panels.
To get to defrost sensor or the air temperature sensor in the No Frost freezer, you need to completely defrost the refrigerator within 24 hours. After this, the back panel of the freezer compartment is removed. It is there, on the fins of the evaporator, that you will find small plastic elements, similar to a bullet or a cylinder, with two wires. There may be several of them: one is responsible for monitoring the temperature of the evaporator, the other is responsible for the temperature of the air in the chamber.
- 🔍 Defrost sensor: Attached directly to the evaporator tubes, often in the lower or middle part, and turns off the heating element when a certain temperature is reached.
- 🌡️ Air sensor: Located in the upper part of the chamber or in the air duct, it does not directly contact the metal of the evaporator, but measures the temperature of the circulating flow.
- ❄️ Sensor in the refrigeration chamber: In two-chamber No Frost, an additional sensor may be located behind the rear wall of the refrigerator compartment, where cold air is supplied.
Replacing such elements requires not only physical access, but also often reprogramming or resetting errors in the electronic module. If after replacement thermistor the refrigerator continues to operate incorrectly, the problem may lie in oxidation of the contacts in the connector or a malfunction of the control unit itself. Unlike mechanics, the accuracy of the resistance is important here, so you need to use only original spare parts or complete analogues.
☑️ Preparation for disassembly No Frost
Specific location in models with a bottom freezer
In the classic layout, where the freezer is located at the bottom, the thermostat is most often located in the upper compartment. This is due to the fact that it is in the fridge compartment that the main operating mode is set, and the freezer operates on the residual principle or through a separate channel. However, in some budget models Indesit there are separate controls, and then the second thermostat can be hidden in the freezer compartment.
If you are looking for where the thermostat is located in a refrigerator Indesit two-chamber with a bottom freezer, pay attention to the side walls. Sometimes manufacturers hide the assembly behind a side plastic trim, especially if the adjustment knob is located unusually low. In such cases, you can remove the panel by unscrewing the screws in the depths of the chamber or by releasing the hidden latches around the perimeter.
Particular attention should be paid to models with freshness zone. They can have additional sensors installed to control the microclimate in a separate compartment. They are usually located on the ceiling of this area or built into the dividing partition. It is more difficult to get to them, since it often requires dismantling the entire internal lining of the chamber.
| Indesit model type | Thermostat location | Sensor type | Difficulty of access |
|---|---|---|---|
| Classic (drip) | Inside the refrigerator compartment, under the ceiling or in the corner | Mechanical (with tube) | Low |
| No Frost (modern) | Behind the rear panel of the freezer (on the evaporator) | Electronic (thermistor) | High |
| With external display | Hidden inside the case, access through the service menu | Electronic (several pieces) | Medium |
| Budget (small volume) | Immediately behind the adjustment knob inside cameras | Mechanical | Low |
Why do some models have two thermostats?
In refrigerators with an air flow control system or in large-volume units, two mechanical thermostats can be installed: one to turn on the compressor, the second to control the fan or chamber switching valve. This allows you to more accurately regulate temperature conditions independently of each other.
Diagnostics of thermostat malfunctions
Before disassembling the refrigerator in search of a replacement, you need to make sure that the problem lies in the thermostat. The symptoms of a malfunction of this unit are quite specific. If the compressor runs continuously without turning off, and a “coat” of ice has formed in the chamber, and the food in the refrigerator compartment is frozen, this is a sure sign that thermostat contacts they are stuck in a closed state.
The opposite situation is when the refrigerator is silent and does not start, may also indicate a breakdown. In this case, the contacts could burn out or oxidize, breaking the circuit. A simple way to initially check a mechanical thermostat is to short-circuit the two wires going to it (after unplugging the refrigerator!). If, after turning on the network and closing the wires, the motor starts, then the problem is in the sensor.
⚠️ Attention: When checking an electronic thermostat (thermistor), the method of shorting the wires does not work and can be dangerous for the control board. To diagnose with a multimeter, you need to “ring” the sensor, checking the change in resistance when the temperature changes (for example, holding it in your hand).
It is also worth paying attention to the condition of the capillary tube. If it is deformed, has traces of corrosion or rust at the entrance to the housing, the tightness of the bellows may have been compromised. In this case, the pressure inside the tube is compared with atmospheric pressure, and the thermostat stops responding to the cold, believing that the chamber is always warm. A visual inspection often provides more information than complex measurements.
Step-by-step instructions for replacing the thermostat
The replacement process begins with completely disconnecting the appliance from the network. For mechanical thermostats in the refrigerator compartment, the algorithm is usually as follows: remove the adjustment knob (by pulling it towards you or unscrewing the screw), unscrew the fastening nut and carefully remove the housing. Then you need to remove the lampshade and the top decorative panel to gain access to the tube insertion point.
The most important stage is working with capillary tube. It must be carefully disconnected from the mounts on the evaporator. Remember or photograph the path of the tube so that when installing a new one, lay it in the same way. The new tube is inserted into the same hole, the body is secured with a nut, and the contacts are transferred from the old sensor to the new one. It is important to reliably insulate the connections if you used twists, although it is better to use the original terminals.
In the case of electronic sensors in the No Frost system, after removing the back panel and disconnecting the old thermistor, a new one is installed in the same place. Often they are fixed with plastic clips or simply inserted into a groove. The main thing is to ensure tight contact of the sensor with the surface it is supposed to monitor. After assembling all the panels, the refrigerator is connected to the network.
- 🛠️ Tools: You will need Phillips and flathead screwdrivers, side cutters (for cutting wires if there are no terminals), electrical tape and a multimeter.
- 📸 Fixation: Take a photo at each stage of disassembly so as not to forget the location of the screws and the path wires.
- 🧊 Defrosting: To replace sensors in No Frost, complete defrosting for at least 24 hours is required, otherwise the ice inside the case will not allow the panels to be removed.
After completing the work, do not rush to load the products. Allow the refrigerator to idle for 4-6 hours to get up to speed and ensure that the on and off cycles are correct. If during this time no extraneous sounds appear and the temperature has stabilized, the repair can be considered successful.
What to do if the tube is of a new length?
Sometimes thermostat analogues have a capillary tube of a different length. Under no circumstances should the excess length be twisted into tight rings or bent. Carefully place the excess in large diameter rings in the free space behind the back wall or under the decorative panel, avoiding contact with moving parts and hot elements.
Frequently asked questions (FAQ)
Is it possible to operate a refrigerator with a faulty thermostat?
Exploitation is possible, but undesirable and dangerous. If the thermostat is stuck, the compressor will work without stopping, which will lead to overheating, breakdown and huge energy consumption. If it doesn't turn on, the food will spoil. As a last resort, some experts advise using an external time relay, but this is a temporary measure.
Where to buy an original thermostat for Indesit?
It is best to look for original spare parts in authorized service centers or specialized stores of spare parts for household appliances. When purchasing, pay attention to the markings (for example, K59, TAM133, etc.), since the external dimensions may be the same, but the temperature response may differ.
Why does the refrigerator freeze less slowly after replacing the thermostat?
Most likely, a thermostat is installed with other response parameters (for example, it turns off the compressor when more high temperature). Also, the reason may be the incorrect location of the capillary tube - it should fit tightly to the evaporator in the same place as the old one.
How to distinguish an electronic sensor from a mechanical one?
A mechanical thermostat always has a long copper tube and clicks when you turn the handle. An electronic sensor (thermistor) is a small plastic element with two thin wires that has no moving parts and no adjustment knobs on the sensor itself.