Failure of the cooling system in a household refrigerator Indesit often takes you by surprise when food begins to deteriorate and ice appears on the walls of the chamber. The main element that controls the climate inside the device is temperature sensor, which sends signals to the compressor to turn it on or off. If you notice that your unit has stopped freezing or, on the contrary, turns vegetables into ice blocks, most likely the problem lies in this small but critical component.
In this article we will look in detail at where exactly the temperature sensor is located in various models of refrigerators Indesithow to get to it without damaging the case and how to carry out initial diagnosis. Understanding the structure of your equipment will allow you to save significant money on calling a technician, since replacing this element is often possible even for a person without special technical education, but with care and a basic set of tools.
Modern refrigeration units are equipped with complex electronics, where each sensor plays the role of a guard of a certain temperature regime. Thermal sensor is not just wiring, but a high-precision measuring device that responds to the slightest changes in thermal background. Its incorrect operation confuses the control board, forcing the motor to wear out or stand idle until the contents of the shelves deteriorate.
Types of thermal sensors in Indesit technology
Before you begin troubleshooting, you need to clearly understand what type of measuring device device you are dealing with, since refrigerators Indesit can use different modifications. The most common are thermoresistors (NTC), the resistance of which varies depending on the temperature of the medium. In older or simpler models, mechanical thermostatsworking on the principle of gas expansion in a capillary tube can be installed.
Electronic sensors are a compact element enclosed in a plastic or metal case, from which they extend two wires. They are highly accurate and allow the electronic control module control temperature in fractions of a degree increments. Mechanical analogues are less accurate, have a greater spread of readings and often emit characteristic clicks when switching compressor operating modes.
What is the difference between NTC and a mechanical thermostat?
NTC sensors (thermistors) change their electrical resistance smoothly and predictably when temperature changes, which allows the electronics to precisely regulate the operation of inverter compressors. Mechanical thermostats work like a switch: they open or close contacts when a certain temperature is reached, which leads to cyclic operation of a conventional compressor.
It is important to note that in two-chamber models Indesit with a system No Frost several sensors can be installed: one in the refrigeration chamber, one in freezer, as well as an evaporator defrost sensor. Each of them is responsible for its own area of work, and the failure of any of them affects the overall cooling efficiency. For example, if the defrost sensor is broken, the evaporator will become covered with ice and the cold will stop flowing into the chamber.
⚠️ Attention: Never try to replace an electronic thermistor with a mechanical thermostat or vice versa. These devices have fundamentally different operating principles and are incompatible with each other’s control boards. Installing an unsuitable component may result in the electronic module burning out.
For accurate diagnosis, you will need to know the markings of your device. The model is usually indicated on a sticker inside the refrigerator compartment or on the back wall. Knowing the model, you can select original analogue with the correct resistance characteristics, which guarantees stable operation of the equipment in the future.
Localization of the sensor in the refrigeration chamber
In the refrigeration compartment of the equipment Indesit The temperature sensor is most often hidden from the user’s eyes so as not to disturb the aesthetics of the interior and protect the element from mechanical damage when loading products. In most cases, it is located behind plastic panel on the back wall of the chamber or built into one of the ceiling air ducts. To gain access to it, you will have to dismantle part of the internal plastic.
The search process begins with a visual inspection. Look for small holes in the plastic or places where wires are visible going deep into the structure. In models with drip system defrosting, the sensor is often located in close proximity to the lampshade or in a niche above the top shelf. In some modifications, it can be hidden inside a plastic box, which is attached with latches.
- 🔍 Inspect the back wall: look for technical holes or places where wires enter.
- 🔍 Check the lampshade area: often the sensor is attached next to the lamp lighting.
- 🔍 Remove the top cover: in some models, access is possible only after dismantling the “ceiling” of the chamber.
- 🔍 Pay attention to the air ducts: in systems Multi Air Flow the sensor may stand in the way of the cold flow.
When dismantling plastic panels, proceed with extreme caution. Plastic in old refrigerators Indesit can be brittle and brittle over time. Use a thin plastic spatula or flathead screwdriver wrapped in cloth to unsnap the latches without the risk of splitting the part. Sudden movements can lead to the appearance of cracks, which will subsequently be difficult to disguise.
After removing the panel, you will see a small element similar to a tablet or cylinder attached to a metal tube or inserted into a special socket. This is exactly what you are looking for thermal sensor. It can be secured with a clamp or simply inserted into the hole with tension. It is important to remember or photograph its position before disconnecting the wires.
Location of the sensor in the freezer compartment
In the freezer compartment of refrigerators Indesit operating conditions are more severe, therefore the location of the sensors here has its own characteristics. In systems No Frost temperature sensors are often mounted directly into the evaporator or mounted on its fins. Getting to them is more difficult, since it often requires complete dismantling of the rear panel of the freezer and removal of the fan.
If we are talking about a freezer with manual defrosting, the sensor is usually located in the upper part, hidden behind a decorative trim. It controls the overall temperature in the chamber volume. Unlike the refrigerator compartment, here the wires can be additionally insulated to avoid them freezing and cracking of the insulation at extremely low temperatures.
To access the sensor in the freezer of the No Frost system, you must:
- Completely defrost the unit (minimum 24 hours).
- Remove all shelves and drawers.
- Remove the back metal or plastic wall.
- Carefully bend back the thermal insulation (if the sensor is recessed in polyurethane foam).
⚠️ Attention: When working in In the freezer, be extremely careful with the defrost heating elements. Do not damage them with a tool and do not turn on the refrigerator in a network with open access to the heater without temperature control, this can lead to a fire.
Often in the freezer there is not only an air temperature sensor, but also defrost sensor. They may look the same, but have different temperature thresholds. If you mix them up when replacing them, you will end up with a non-working defrost system or a constantly running compressor. Markings on the body or the color of the wire insulation will help to distinguish them.
Instructions for dismantling and access
The dismantling process to gain access to thermal sensor requires preparation of tools and compliance with the sequence of actions. You'll need Phillips and flat-head screwdrivers, possibly socket wrenches to remove some fasteners, and a multimeter to check later. The main rule is safety and no haste.
The first step should always be to completely turn off the refrigerator Indesit from the electrical network. This will protect you from electric shock and prevent short circuits if the wiring is accidentally damaged during operation. Then empty the chambers of food and remove all removable elements: shelves, drawers, baskets.
☑️ Preparation for dismantling
Next follows careful removal of the plastic panels. In refrigerators Indesit they are often secured with hidden latches. Do not use excessive force. If the panel cannot be removed, check to see if there are any loose screws that may be hidden under decorative plugs or stickers. After removing the panel, access to the internal “filling” will open, where the sensor is located.
The sensor itself is usually fixed in a metal sleeve or pressed to the evaporator tube. To remove it, you may need to carefully bend the retaining tab or loosen the clamp. The wires coming from the sensor can be threaded through holes in the housing or foamed. If the wire is foamed, it must be very carefully released without damaging the insulation or breaking the tightness of the polyurethane foam layer.
Diagnostics and testing with a multimeter
Before buying a new part, you need to make sure that the problem is in the sensor, and not in the control board or wiring. For this purpose, multimeteris used, switched to the resistance measurement mode (Ohms). Diagnostics allows you to determine with high accuracy the serviceability of an element without installing it in the unit.
The test process is as follows: disconnect the sensor connector from the control board or bite off the wires (if you plan to replace it and the old data sensor has already been removed). Connect the multimeter probes to the sensor contacts. At room temperature (about 20-25°C), a working NTC thermistor should show a certain resistance, usually in the range from 4 to 10 kOhm, depending on the model Indesit.
For more accurate diagnostics, you can place the sensor in a container with water of a known temperature (for example, with melting ice - 0°C) and monitor the change in readings on the device screen. The resistance should increase smoothly when cooling and fall when heating. If the device shows an open circuit (infinity) or a short circuit (zero), the part faulty needs replacement.
| Medium temperature (°C) | Expected resistance (kOhm) | Element status | Action |
|---|---|---|---|
| +25°C (Room) | ~5.0 - 6.0 kOhm | Normal | Operation |
| 0°C (Melting Ice) | ~15.0 - 16.5 kOhm | Normal | Operation |
| Any | Infinity (1) | Break | Replacement |
| Any | 0.00 kOhm | Short circuit | Replacement |
Replacement and installation of a new element
Replacement thermal sensor in the refrigerator Indesit —the procedure is technically simple, but requires attention to detail. The main condition is that the new element must have identical characteristics (nominal resistance and B-parameter). Using an unsuitable analogue will lead to incorrect operation of the refrigerator, even if it physically fits into place.
Installation is carried out in the reverse order of dismantling. Carefully insert the new sensor into the socket or secure it to the evaporator tube using standard fasteners or heat-resistant sealant, if necessary. Make sure that the contact between the sensor and the surface whose temperature it is measuring is tight. Place the wires in standard channels, avoiding kinks and pinching by doors or moving mechanisms.
After connecting the wires to the connector, check the reliability of the contact again. If the connector has a locking tab, it should click into place. Reassemble the plastic panels in the reverse order, making sure that all the latches are in place and there are no gaps through which cold can escape.
⚠️ Attention: When installing a new sensor, avoid touching its sensitive element with your hands. Fatty traces can affect heat transfer and reading accuracy. Hold the part by the body or wires.
After assembly, turn on the refrigerator. For the first few hours, the unit will work in enhanced mode, reaching the set temperature. At this time, do not load the chambers with products so as not to create unnecessary heat load. Monitor the operation of the compressor: it should turn on and off periodically.
Frequently asked questions and problems
Is it possible to temporarily short-circuit the sensor to make the refrigerator work?
Theoretically, short-circuiting or installing a resistor with a fixed resistance can make the compressor work constantly. However, this dangerous: the refrigerator will not turn off, which will lead to freezing of food in the refrigerator compartment, freezing of the evaporator and possible failure of the compressor due to overheating. This solution is only for an emergency short-term check.
Why does the refrigerator not turn off after replacing the sensor?
There may be several reasons: a sensor is installed with incorrect resistance parameters, loose contact in the connector, or the problem is not in the sensor, but in the control board or compressor relay. It is also possible that the seal of the chambers is broken or the door seal is faulty, and the unit cannot gain temperature.
How often do you need to change the temperature sensor?
The service life thermal sensor usually coincides with the service life of the refrigerator itself. It is not consumable. Replacement is required only in case of physical damage or electrical breakdown, which rarely happens, usually due to voltage surges or aging of the insulation.
Does humidity affect the operation of the sensor?
The sensor itself is sealed, but oxidation of the contacts in the connector due to high humidity may cause incorrect readings. If you see traces of corrosion on the terminals, they must be cleaned with alcohol and treated with contact spray before installing a new element.