Unexpected defrosting of the contents of the refrigerator compartment is always stressful and risks losing food. Often the cause is a failure of the thermostat, which stops giving a signal to the compressor to turn on or, conversely, does not turn off the unit. Owners of household appliances thermostat (thermostat), which stops giving a signal to the compressor to turn on or, conversely, does not turn off the unit. Owners of household appliances Indesit often encounter this problem, especially if the refrigerator is several years old.
Independent replacement of this element is quite realistic for a person who knows how to hold a screwdriver in his hands and follow basic safety rules. However, the process requires care, since incorrect connecting contacts can lead to a short circuit or failure of the compressor. In this article we will analyze all the nuances of diagnostics and installation.
Before you start disassembling, you need to make sure that the problem lies in the thermostat, and not in a freon leak or a malfunction of the start relay. If the compressor does not start at all, but is working properly, or works non-stop, without turning off for hours, then the probability of breakdown temperature sensor is extremely high. Let's look at the process in detail.
Diagnostics of thermostat malfunction
The first step should always be an accurate diagnosis. Symptoms may be similar to other breakdowns, so it is important to rule out obvious options. If the refrigerator Indesit hums, but there is no cold, or it is “silent” for days, it is worth checking the operation of the thermostat. The main sign of a malfunction is often the absence of a characteristic click when turning the temperature control knob.
For a more accurate check, you will need a multimeter. You will need to get to the thermostat, remove the wires from it and “ring” the contacts in different positions of the handle. In the “off” position, the circuit should be broken, and when turned towards cooling, it should be closed. If the device shows infinity resistance in both cases or, conversely, zero constantly, the part requires replacement.
⚠️ Attention: Before any manipulations with electrical components, be sure to unplug the refrigerator! Working under voltage is deadly and can lead to electric shock.
It is also worth paying attention to the condition of the capillary tube that comes from the thermostat. If it is damaged or has signs of corrosion, the tightness of the system is broken and the gas inside has evaporated. In this case, even a working electrical part will not save the situation. Capillary It must be intact, without creases or cracks.
Preparation for replacement and selection of components
The success of the repair largely depends on the correctness of the selected spare part. Thermostats for refrigerators Indesit may differ in the length of the capillary tube, type of contacts and operating temperature range. Using the wrong model will lead to incorrect operation: either the food will freeze or the temperature in the chamber will be too high.
Remove the old thermostat and carefully study the markings on the case. Typically this is an alphanumeric code starting with letters (eg K, TAM, DANFOSS). The length of the capillary tube is also important - it should not be shorter than the original, otherwise the sensor will not reach the desired zone in the evaporator. If the tube is too long, you can carefully twist it into a ring, but do not bend it.
For work you will need a minimum set of tools:
- 🔧 Screwdrivers (Phillips and flat) for removing panels.
- 🔦 Flashlight for illuminating the internal space.
- 🔌 Pliers for carefully removing the terminals.
- 📏 Ruler or tape measure for measuring the length of the capillary.
Don't forget to prepare a container to collect possible drops of water that may accumulate in the niche of the thermostat. It is also recommended to take a photo of the wiring diagram before disconnecting them. This will help avoid confusion when installing a new element, especially if the color markings of the wires have faded.
Connection diagram and contact marking
One of the most critical steps is the correct connection of the wires. In different refrigerator models Indesit the diagram may differ slightly, but the general principle remains the same. The thermostat acts as a switch that opens or closes the compressor power supply circuit depending on the temperature.
Usually three or four wires go to the thermostat. Two of them go to the light bulb (if it is connected to the thermostat), and the other two go directly to the compressor circuit break. It is important not to confuse power contacts with control contacts. On the body of most regulators there are markings, for example 3-4 or 6-3, indicating pairs of contacts that close when the temperature drops.
Consider a typical contact correspondence table for popular models of thermostats installed in Indesit equipment:
| Type thermostat | Close contacts | Open contacts | Feature |
|---|---|---|---|
| K50 (Danfoss) | 3 - 4 | 3 - 6 | The most common option |
| TAM 133 | 3 - 4 | 3 - 6 | Analogous to K50, often interchangeable |
| K59 | 3 - 4 | 3 - 6 | Used in NoFrost systems |
| Single contact | 2 contacts | - | Only open circuit of the compressor |
If you see that the contact arrangement on the new thermostat is different from the old one, do not panic. The main thing is to understand the logic of operation: which contacts should be connected when it gets cold. In most cases, for the refrigerator compartment, it is necessary to ensure that the circuit is closed when cooling. Grounding The thermostat housing (if there is a separate screw) also cannot be ignored, this is a safety issue.
What will happen if the contacts are mixed up?
If you apply voltage to the contacts, designed for light bulbs, the internal circuitry may burn out or short circuit. If the power contacts are mixed up, the compressor may either not start or run without stopping, ignoring the temperature settings.
Step-by-step instructions for installing a thermostat
The process of installing a new temperature controller requires care, especially when working with a capillary tube. It is very thin and easily damaged. Any microcrack will lead to leakage of sensitive gas, and the thermostat will stop responding to temperature changes.
First install the thermostat in its seat. Secure it with standard fasteners or screws that were removed during dismantling. Make sure the housing fits snugly and does not wobble. Compressor vibration should not be transmitted to the thermostat, as this can cause false alarms or contact rattling.
Next comes the most important step - laying the capillary tube. In models Indesit with a weeping evaporator, the end of the tube is usually inserted into a special hole in the rear wall of the chamber or attached to the evaporator with a metal strip. The immersion length must correspond to the factory parameters (usually 20-30 cm inside the channel).
Checklist for checking correct installation:
- ✅ The capillary tube is not pinched or has any creases.
- ✅ The end of the tube is tightly pressed to the evaporator for better heat exchange.
- ✅ The wires are laid so as not to touch moving parts or hot components.
- ✅ All terminal connections are tight and do not loose.
After the mechanical installation, we move on to the electrical part. Connect the wires according to the photographs or diagram you took earlier. If you are using terminal blocks, make sure they click into place. Poor contact will cause heating and melting of the insulation.
☑️ Check before turning on
Nuances for different Indesit models
Refrigerators Indesit were produced in various modifications, and the design of the thermoregulation unit may differ. In classic two-compartment models with one compressor, the thermostat is usually located in the ceiling lamp or under the top cover inside the refrigerator compartment. Access to it often requires removing decorative trims.
In system models NoFrost the situation is more complicated. There the thermostat can be combined with defrost sensors or located in the air duct. Replacement in such systems requires partial disassembly of the rear wall of the freezer. Be careful with plastic latches - they often become brittle with time and cold.
⚠️ Attention: The design of refrigerators may vary depending on the year of manufacture. If you see that the location of the components differs from that described, check the technical documentation of the specific model on the manufacturer’s official website.
Particular attention should be paid to models with electronic control. In them, a mechanical thermostat may be absent as such; its function is performed by electronic temperature sensors. If your Indesit door has a display, most likely, replacing the mechanical “twist” will not help you - you need diagnostics of the electronic module.
First start-up and setting the temperature
After everything is connected and assembled, the moment of truth comes. Plug in the refrigerator. You should hear the relay click and the compressor start. If this does not happen, check the connection diagram again. The thermostat may be in the “off” position (usually the extreme counterclockwise position of the knob).
Allow the unit to operate for 30-40 minutes. During this time, the temperature in the chamber should begin to decrease. Check the thermostat operation: wait until the refrigerator gets cold and turns off. If it turns off and turns on again on its own after a while, the repair was successful.
For final adjustments, use the built-in thermometer or place a regular thermometer in a glass of water. The optimal temperature in the main chamber is +2...+4°C. Adjust the position of the thermostat knob until you achieve stable maintenance of these values. You should not turn the regulator to the maximum, this will increase the load on the compressor.
Frequently asked questions (FAQ)
Can I use a thermostat from another brand? refrigerator?
Technically possible if the mounting dimensions, capillary tube length and temperature range match. However, it is better to look for original spare parts or complete analogs designed specifically for Indesitto avoid problems with setup.
Why does the new thermostat click, but the refrigerator does not turn on?
This may indicate a malfunction of the compressor start relay, the motor itself, or an open circuit between the thermostat and the compressor. Also check whether voltage is supplied to the thermostat input contacts.
Do you need to defrost the refrigerator before replacing?
Yes, complete defrosting is required. During operation, access to the evaporator may be required, and the presence of ice will complicate the installation of the capillary tube and can lead to damage to the plastic elements.
How can you understand that the thermostat is “lying” and shows the wrong temperature?
If the food in the chamber is clearly frozen or, conversely, spoils, although the knob is set to the middle value and the compressor operating cycle does not correspond normal (too short or too long), which means the calibration is broken and a replacement is needed.
Is it dangerous to leave a refrigerator with a faulty thermostat?
Yes. If it does not turn off the compressor, the motor may burn out from overload. If it doesn’t turn it on, the food will defrost. In addition, faulty electrics are a risk of fire or short circuit.