When refrigerator Indesit the temperature regime stops working correctly, the first suspicious element is the thermostat. This small device is responsible for turning the compressor on and off, maintaining a given level of cold. If you notice that food begins to deteriorate or, on the contrary, turn into ice blocks, and the compressor works without interruption or does not start at all, most likely the problem lies in this part.
Owners are often lost, trying to understand where exactly this important unit is hidden, since manufacturers of household appliances rarely make access to it obvious. In models Indesit the location of the thermostat can vary significantly depending on the year of manufacture and the type of defrosting system. In older models with a “crying” evaporator, it is located inside the refrigeration chamber, while in modern No Frost you need to look for it in a completely different place.
Understanding the design of your unit is half the success of the repair. You should not immediately call a specialist if you have minimal skills in working with tools. Competent diagnostics will save money and time. Next, we will analyze in detail the algorithms for searching and replacing the sensor for various modifications of equipment of this brand.
The principle of operation of the thermostat in Indesit systems
The thermostat, or thermostat, is an electromechanical or electronic device that reads the temperature inside the chambers and sends a signal to the compressor. Classic models Indesit use a bellows tube filled with freon or an analogue gas. When the temperature changes, the volume of gas changes, which leads to the opening or closing of electrical contacts.
Electronic versions, which are more often found in new lines, operate on the basis of thermistors. They change their resistance depending on heating or cooling. Such sensors are more accurate, but require special equipment for full diagnostics. Mechanical devices can be checked with a multimeter in continuity mode.
Failure of this element leads to a disruption of the cooling cycle. The compressor may run non-stop, trying to achieve a non-existent cold, or stand off, allowing the temperature to rise. In both cases, thermostat is the main suspect.
⚠️ Attention: Before any manipulations with the electrical components of the refrigerator, be sure to disconnect the device from the network. Working with 220V current without proper training is deadly.
It is also worth noting that in two-chamber models, the thermostat usually controls only the refrigeration chamber. The freezer operates on the residual principle or has its own separate sensor if the control system is electronic. Therefore, failure of the regulator often manifests itself in the upper compartment.
Where to look for a thermostat in models with a drip system
In classic refrigerators Indesit with manual or drip defrosting, the thermostat is traditionally located inside the refrigerator compartment. This is the most common scheme for equipment produced before the mid-2010s. Finding it is quite easy if you know where to look.
It is usually built into a plastic control panel that is located on the top of the camera, often above the door or in a corner. On the front panel of this plastic box there is a mode switching knob (from “Min” to “Max” or digital designations). It is behind this handle that the mechanism itself is hidden.
To get to the insides, you need to:
- 🔌 Carefully remove the regulator handle by pulling it towards you (sometimes you need to slightly pry it with a flat screwdriver).
- 🔧 Unscrew the screws securing the plastic case to the chamber wall.
- ❄️ Carefully move the housing to gain access to the electrical contacts and bellows tube.
The bellows tube in such models is laid along the inner wall and secured with special clips. It should not be kinked or damaged. The end of the tube is often hidden behind decorative plastic or is located in the evaporator area.
In some modifications, for example, series Indesit C or ER, the thermostat can be moved closer to the lampshade. In this case, you will have to remove the light bulb to gain access. Be careful with the wiring so as not to damage the insulation when removing the unit.
The location of the sensor in No Frost refrigerators
The situation with system models No Frost is radically different. Here the thermostat (or defrost sensor, which is often confused with the main regulator) is hidden from the user's view. In such systems, temperature control is often carried out by an electronic module, and mechanical sensors may be absent as a class.
If your Indesit No Frost does have a mechanical thermostat installed, it is most often hidden behind a plastic panel on the ceiling of the refrigerator compartment or in a niche behind a lighting lamp. However, in 90% of cases in such models, air sensors mounted on the air ducts are responsible for the temperature.
To access them, more serious disassembly will be required:
- 🛠️ Remove all shelves and drawers from the refrigerator compartment.
- 🔩 Remove the back wall or top panel (depending on from the model).
- 💨 Find the air duct through which cold air comes from the freezer.
It is on this air duct that the sensor is attached. It is a small plastic cylinder with two wires. Unlike mechanical analogues, it does not have a long gas tube. Its task is to transmit data on air temperature to the electronic control unit.
⚠️ Attention: The design of No Frost refrigerators is complex and individual for each series. Parts may be arranged non-standardly. If you are not confident in your abilities, it is better to check the official diagram for your specific model.
It is important not to confuse the temperature sensor with the defrost sensor. The latter is usually located on the evaporator in the freezer and is responsible for turning on the heating element. Their functions and resistance parameters differ, so interchangeability is excluded.
Why do No Frost sensors often fail?
In No Frost systems, sensors are constantly exposed to conditions of high humidity and temperature changes. Condensation can oxidize contacts, and defrosting cycles create thermal stress in materials, which leads to changes in resistance and disruptions in readings.
Fault diagnosis: symptoms and testing
Before buying a new part, you need to make sure that the problem is in the thermostat. Symptoms may be similar to a compressor failure or freon leak. The main sign of a malfunctioning regulator is incorrect operation of the compressor.
If the motor hums continuously without turning off, and the temperature in the chamber drops below zero, freezing vegetables, this is a sure sign of contacts “sticking” in the “on” position. The opposite situation - the refrigerator is silent, the light is on, but there is no cold - indicates that the circuit is open and does not close even when the temperature rises.
Checking the mechanical thermostat is done with a multimeter:
- 📏 Remove the thermostat and disconnect the wires.
- ⚡ Switch the multimeter to the continuity or resistance measurement mode.
- 🌡️ Place the sensitive part (bellows tube) in the cold (you can use the freezer for 15-20 minutes).
- 🔊 Test the contacts: in the cold they should close (a sound will appear or the resistance will become zero).
For electronic sensors the technique is different. Their resistance changes smoothly depending on temperature. It is necessary to check the multimeter readings at different temperatures with reference tables for a specific type of thermistor. If the resistance is infinite or equal to zero at any temperature, the sensor is faulty.
| Symptom | Probable cause | Action |
|---|---|---|
| The compressor does not turn on | Open circuit thermostat | Ring the contacts, replace the part |
| The refrigerator freezes too much | The contacts do not open | Replace the thermostat |
| Frequent on/off | Incorrect sensor readings | Check calibration or replace |
| Sparking inside the control unit | Burning of contacts | Urgent replacement to avoid fire |
It is also worth checking the bellows tube for mechanical damage. If the gas has escaped through a microcrack, the thermostat will stop responding to temperature changes. It is difficult to determine this visually, so it is easier to immediately carry out an electrical check.
Step-by-step instructions for replacing the thermostat
Replacing the thermostat in refrigerator Indesit is a procedure that requires accuracy, but not necessarily the highest qualifications. The main thing is to follow the sequence of actions and not damage fragile structural elements.
The replacement process is as follows:
- Disconnect the refrigerator from the power supply and defrost it for 24 hours (for No Frost models this is critical).
- Remove the plastic cover hiding the thermostat using a screwdriver.
- Take a photo of the wiring diagram so as not to confuse them during assembly.
- Disconnect the wires and carefully remove the old thermostat along with the tube.
- Install the new device, securing the tube in the same clips as the old one.
Pay special attention to the tightness of the tube passing through the chamber wall. If the model involves the passage of the tube outside (into the engine compartment), the exit point must be carefully sealed so that warm air does not get inside.
Sequence of actions:1. Power off
2. Removing the regulator handle
3. Dismantling the housing
4. Photo recording of wires
5. Replacing an element
6. Assembly and test
After installation, turn on the refrigerator and let it run for several hours. Do not load products immediately. Monitor the on and off cycles. If the compressor turns off when the desired temperature is reached and turns on when it rises, the repair was successful.
☑️ Check after replacement
Frequent repair mistakes and expert advice
When repairing refrigerators yourself Indesit Amateur craftsmen often make typical mistakes that can lead to repeated breakdowns or worsening of the situation. One of the most common is ignoring the length of the capillary tube.
If you install a thermostat with a shorter or longer tube than required, it will not work correctly. A short tube will not reach the evaporator area and will show the wrong temperature, while a long tube may fold into a coil, which is dangerous.
Another mistake is poor contact insulation. In conditions of high humidity inside the chamber, even the slightest gap in the insulation will lead to oxidation and corrosion. Use only quality terminals and heat shrink.
⚠️ Warning: Never attempt to adjust the factory settings of a new thermostat by turning the hidden screws on the housing. This will disrupt the calibration, and the device will operate unpredictably.
Also, you should not use universal thermostats without first checking their parameters. Although they may fit, their temperature range may not match your compressor's requirements, causing it to overload.
If you are replacing a mechanical thermostat with an electronic one (or vice versa), make sure the wiring diagram allows for this. In some cases, it is necessary to resolder the wires or install additional adapters.
Is it possible to temporarily do without a thermostat?
Technically, you can close the contacts directly so that the refrigerator freezes constantly. But this is an emergency measure! The compressor will work non-stop, which will lead to rapid wear and huge energy consumption. Use this method only to save food before the technician arrives.
How often do you need to change the thermostat in the Indesit refrigerator?
The thermostat does not have a strict service life and is replaced only after a breakdown. On average, mechanical regulators last 5-8 years, electronic sensors can last up to 10 years or more. The frequency of replacement depends on the intensity of use and the stability of the voltage in the network.
Why does the refrigerator freeze, but the thermostat does not turn off the compressor?
This indicates that the thermostat contacts are “burnt” in the closed state or the bellows has lost its tightness and has stopped responding to gas expansion. In both cases, the element must be replaced, since it cannot be repaired.
Is it possible to use a thermostat from another refrigerator model?
The use of analogues is possible if the mounting dimensions, capillary tube length and temperature response range are the same. However, it is better to look for the original spare part number or its full analogue recommended by the manufacturer.
What to do if, after replacing the thermostat, the refrigerator does not turn on?
Check that the wires are connected correctly (check the photo before disassembly). Make sure the new thermostat is working properly and opens at room temperature. Also check the integrity of the fuses and the start relay.
Does the ambient temperature affect the operation of the thermostat?
Yes, if the refrigerator is in an unheated room at a temperature below +10°C, the thermostat may not turn on the compressor, since it will consider that it is already cold enough inside. For such conditions, special climate classes of equipment are required.