Sudden defrosting of food or, conversely, turning fresh vegetables into ice blocks is a sure sign that the temperature control system has failed failure. In brand refrigerators Indesit a mechanical or electronic thermostat is most often responsible for maintaining a given mode. This small but critically important unit closes and opens the electrical circuit of the compressor depending on the temperature inside the chambers.
Before calling a technician or buying a new spare part, it is necessary to carry out proper diagnostics to exclude other possible causes of failure, such as a freon leak or a malfunction of the compressor motor itself. Checking the thermostat is a procedure available to the home to a master with a minimum set of tools and basic knowledge of electrical engineering. Correct identification of the problem will save your budget and time.
In this article we will analyze in detail the algorithm for identifying thermostat defects, consider methods of visual inspection and testing with a multimeter. You'll learn how to differentiate between sensor failure and wiring or start relay problems. The accuracy of diagnostics at this stage directly affects the success of subsequent repairs of household appliances.
Main signs of a thermostat malfunction
Understanding the symptoms allows you to reduce the time of searching for a breakdown. When Indesit refrigerator thermostat stops working correctly, this manifests itself in a change in the usual operating mode of the unit. Most often, users are faced with the fact that the refrigerator stops turning off, working without stopping, which leads to increased energy consumption and overheating of the compressor.
The opposite situation is also possible: the compressor does not start at all, and the chamber becomes warm. In some cases, the on/off cycle becomes too short, which is also harmful to the equipment. Below is a list of the main signs indicating the need to check the sensor:
- 🧊 Food in the refrigerator compartment freezes, ice crusts appear on the back wall even with minimal regulator settings.
- 🔊 The compressor operates continuously, without turning off for rest, while the temperature inside can be either normal or reduced.
- 🔥 It’s warm in the refrigerator compartment, the food is spoiling, and the motor is silent, although the light is on and power is supplied to the outlet.
- ⚡ Frequent clicks of the relay and attempts to start the motor, which do not lead to cooling, may indicate that the thermostat contacts do not close.
⚠️ Attention: If the refrigerator runs continuously but does not freeze, the problem may not be with the thermostat, but with a refrigerant leak. In this case, replacing the sensor will not solve the problem.
It is important to pay attention to the position of the regulator knob. If, when turning the knob to the “maximum” or “minimum” position, the nature of the engine’s operation does not change, this is a clear signal of a malfunction in the electrical part of the device. In electronically controlled models, failures may appear as errors on the display, but mechanical thermostats require manual checking.
Sometimes the fault lies in the bellows tube itself, which transmits the temperature. If it is deformed or has lost its tightness, the sensor does not receive correct data about the state inside the chamber. Diagnostics of the thermostat in such cases, it requires a careful inspection of not only the electrical contacts, but also the physical condition of the capillary tube.
Preparation for diagnostics and safety precautions
Any work related to disassembling electrical appliances and checking electrical circuits require strict adherence to safety measures. Before you begin checking the thermostat, you must completely turn off the power to the refrigerator. Unplug the power cord from the outlet - this is the first and most important rule, ignoring which may result in electric shock.
To carry out the work you will need a minimum set of tools. The main device will be a multimeter (tester) configured to measure resistance (Ohm) or test continuity. You will also need screwdrivers (Phillips and flathead) to dismantle the panels and, possibly, pliers to carefully disconnect the terminals.
☑️ Preparation for testing
It is recommended to take a photo of the wire connection diagram to the thermostat in advance before disconnecting them. The color marking of wires for different models Indesit may differ, and it is very easy to confuse the contacts during assembly. The photograph will become your insurance during re-installation.
Ensure good lighting of the work area. You will have to work in confined spaces, often inside the refrigerator cabinet or behind protective panels. Having a flashlight or headlamp will greatly facilitate the process of inspecting and manipulating small parts.
⚠️ Attention: Never try to measure resistance or continuity of a live circuit. This is guaranteed to lead to failure of the multimeter and can be life-threatening.
If you plan to check the thermostat by removing it, prepare a container for defrosting if there is ice left in the chamber. It is also worth laying dry rags on the floor to prevent water from getting on the flooring. Accuracy at the preparation stage is the key to successful and safe repairs.
Removing the thermostat in Indesit refrigerators
The location of the thermostat depends on the model of your refrigerator Indesit. In most single-compressor models it is located inside the refrigeration chamber, and in double-compressor models it is often located outside, in the upper part of the case, next to the defrost button or lampshade. Let's consider both options.
If the regulator is located inside the camera, it is usually hidden under a plastic casing or located next to the lamp shade. To get to it, you need to remove the top cover of the refrigerator compartment or carefully pry off the plastic cover. The fastenings can be on latches or screws that need to be unscrewed.
For models with an external location (often this is the top panel above the door of the refrigerator compartment), the algorithm is as follows:
- 🔧 Remove the top decorative panel by unscrewing the mounting screws (usually there are two or four).
- 💡 Carefully remove the lampshade if it interferes with access, having first disconnected the wires.
- 🔌 Find the thermostat itself - this is a plastic box with wires suitable for it and a capillary tube going deep into the body.
- 📸 Take a photo of the connection and number the wires if they are not color-coded or it is erased.
After gaining access to the contact group, you must disconnect the terminals. This must be done carefully, holding the wire at the base of the terminal so as not to break the wires. If the terminals are oxidized or stuck, you can carefully clean them or use WD-40 spray, but it is better to avoid getting chemicals on the plastic.
Difficulties in removing the capillary tube
If you plan to completely remove the thermostat for replacement, keep in mind that the capillary tube is very thin and fragile. It should not be bent at an acute angle or pulled with force. In some Indesit models it is secured in a special hole with a latch that needs to be released. If the tube is damaged, the thermostat will have to be replaced entirely, since it cannot be repaired.
In some cases, to completely remove the device, partial disassembly of the inner wall of the refrigerator is required to free the end of the capillary tube. If you are not confident in your abilities, it is better to limit yourself to checking the contacts without complete dismantling, ringing the circuit right on the spot, if the length of the wires allows.
Methods of checking with a multimeter and visual inspection
The most reliable method of diagnosis is using a multimeter. This device allows you to accurately determine whether the circuit is closed when the temperature changes. First, carry out a visual inspection: there should be no cracks, signs of burning or melting on the body. The contacts inside must be clean, free of oxides and carbon deposits.
To check operability of the thermostat Using a multimeter, switch the device to resistance measurement mode (200 Ohm range or continuity mode). Connect the probes to the contacts that go to the compressor (usually contacts 3 and 4 or 3 and 6, depending on the markings). At room temperature, the contacts should be closed, and the device should show zero or emit a beep.
Next, you need to check the circuit opens. To do this, the thermostat (or its sensitive tube) needs to be cooled. At home, this can be done by placing the sensor in the freezer for 15-20 minutes or placing an ice pack on it. After cooling, the contacts should open and the resistance should become infinite (one on the digital multimeter screen).
| Sensor status | Temperature | Multimeter readings | Action |
|---|---|---|---|
| Normal | Room (+20°C) | 0 Ohm (circuit closed) | Good |
| Normal | Cooling (below -5°C) | ∞ (circuit broken) | Good |
| Fault | Room | ∞ (circuit broken) | Replacement |
| Fault | Cooling | 0 Ohm (circuit closed) | Replacement |
If when At room temperature the circuit does not ring, which means the contacts inside are burnt or the mechanism is jammed. If, after cooling, the circuit continues to ring, the thermostat is “stuck” and does not give the command to turn off the compressor. In both cases, it is necessary replacement of the thermostat.
⚠️ Attention: When checking an electronic thermostat (with a digital display), the dialing method is not suitable. Such sensors (thermistors) are checked by measuring their resistance, which should change smoothly with temperature changes, according to the manufacturer’s rating table.
Alternative methods of testing without instruments
What to do if you don’t have a multimeter at hand? There is a “folk” test method that allows you to determine the malfunction with a high degree of probability. It is based on direct closure of the circuit, bypassing the thermostat. This method helps to understand whether the compressor itself and the start relay are alive.
To do this, you need to connect the wires that went to the thermostat directly (after turning off the power to the refrigerator!). Usually the wires coming from the network and going to the compressor relay are connected. After connection, plug in the refrigerator. If the motor hums and starts working, it means that everything is in order with the compressor and relay, and the problem is in the thermostat.
However, this method has a serious drawback: the refrigerator will work continuously until you open the circuit manually. Therefore, it cannot be used for long-term use. This is a diagnostic measure only.
Another indirect method is to check the reaction to turning the handle. If, when rotating the regulator from minimum to maximum, you do not hear a characteristic click (in silence, with your ear close to the body), this may indicate that the mechanism does not work. Although in noisy refrigerators this click may not be heard.
Also pay attention to the condition of the bellows tube. If it has creases, swelling or signs of corrosion, then even a working electrical part will not be able to control the temperature correctly. The deformed tube does not transmit the gas or liquid pressure inside the bellows, and the contacts do not open.
Replacing the thermostat and setting up the operation
If the diagnostics confirm the malfunction, the only option is replacement. Buy a thermostat with exactly the same markings as your old device. Different models Indesit may differ in the length of the capillary tube, type of fastening and temperature range of operation.
The installation process is the reverse of the dismantling process. Carefully insert the bellows tube into the mounting hole, being careful not to damage it. Connect the wires according to the photographs or color markings you took earlier. Securely fasten the device body.
After assembling and turning on the refrigerator, it will take time for the first freeze (from 4 to 12 hours). Do not load the camera with food on the first day. Check the operation of the cycle: the refrigerator should reach the temperature and turn off.
If after the replacement the problem persists (the refrigerator does not turn off or turn on), perhaps the problem is not with the thermostat. Check the compressor start relay, the motor itself, or the system for leaks. But in 80% of cases of the described symptoms, the thermostat is the culprit.
Is it possible to repair the thermostat yourself?
Theoretically, if the problem is burnt contacts, they can be cleaned. However, the thermostat housing is often soldered or riveted, and the seal of the bellows is broken when opened. Experience shows that repairs are temporary and unreliable. It’s easier and safer to buy a new sensor.
Why does the Indesit refrigerator freeze too much?
Most often this happens due to “sticking” of the thermostat contacts in the closed state. The compressor receives power constantly and does not turn off. Less commonly, the reason is incorrect setting of the regulator or a violation of the door seal.
Where is the thermostat located in a two-chamber refrigerator?
In most two-chamber Indesit models, the thermostat is located outside, in the upper part of the case above the door of the refrigerator compartment, under a plastic cover. In single-chamber models, it is often located inside, next to the light bulb.
What do the numbers on the thermostat handle mean?
The numbers from 1 to 5 (or 7) indicate the cooling intensity, where 1 is the minimum cold, and the maximum number is the strongest mode. The “0” or “Off” position completely turns off the compressor.