Sudden stoppage of operation refrigeration unit or, conversely, its continuous operation without stopping often indicates a failure of the temperature control system. In refrigerators Indesit a special device is responsible for maintaining a given mode - a thermostat (or thermostat). It is he who commands the compressor to turn on or off depending on the temperature inside the chamber. If you notice that food has begun to deteriorate or, on the contrary, freeze, and the unit itself hums without interruption or is silent, most likely the problem lies in this unit.
Replacing the thermostat is one of the most common procedures in repairing household appliances, which you can do yourself if you have basic skills and tools. Independent intervention allows you to save a significant amount that would have to be paid to the master for calling and working. However, before you start disassembling, you need to make sure that it is thermostatthat is faulty, and not the compressor or start relay. In this article we will analyze in detail the diagnostic process, selection of components and a step-by-step algorithm for replacing the sensor in various refrigerator models Indesit.
Safety is the first rule of any repair. Before starting any work on dismantling the refrigerator components, it is necessary to completely disconnect the device. Unplug the power cord from the outlet. This is critical because you will be working with live electrical contacts and wires while the unit is turned on. Ignoring this rule may result in serious electrical injury or short circuit.
Diagnosing a thermostat malfunction
Before disassembling the refrigerator and purchasing new parts, you should conduct an initial diagnosis. Symptoms of a thermostat failure can be different, but most often they come down to incorrect temperature conditions. If the compressor does not turn on at all, even when the chamber is warm, or runs non-stop, turning the chamber into a freezer, these are direct indications of a sensor malfunction. It is also worth paying attention to the nature of the clicks: if you do not hear a characteristic sound when changing the position of the control knob, the mechanism could be jammed.
For a more accurate check, you can use a multimeter. You will need to remove the thermostat and “ring” its contacts. In normal condition (at room temperature), the contacts should be closed, and the device will show zero or a resistance value close to it. If you put the thermostat sensing tube in cold water (simulating cold in the chamber), the contacts should open and the resistance will become infinite. Lack of response to temperature changes indicates that mechanism requires replacement.
⚠️ Attention: If you are not confident in your skills in working with electrical measuring instruments, do not try to carry out diagnostics with a multimeter at random. An error in measurements can lead to a false conclusion and unnecessary purchase of spare parts.
There is also a simple visual inspection method that is often used by craftsmen. If, when you turn the thermostat knob from the “off” position to the “min” position, you do not hear a click and the light does not light up (if it is designed and working properly), this may indicate a problem. However, this method does not provide a 100% guarantee, since the light bulb could burn out regardless of the thermostat. Therefore, an integrated approach to diagnostics is the most correct solution before starting repair.
Necessary tools and preparation
To successfully replace the thermostat in the refrigerator Indesit you will need a minimum set of tools. You don't need to be a professional engineer to cope with this task, but having the right equipment will greatly simplify the process and protect the unit body from damage. The main tool will be a screwdriver, but depending on the model of your refrigerator, you may need both a Phillips and a flat variation.
In addition to screwdrivers, prepare the following tools and materials:
- 🔧 Pliers or pliers - for carefully removing the terminals from the thermostat contacts.
- 🔪 Knife or scalpel - may be needed to carefully remove plastic plugs or strip contacts (use with caution).
- 🧤 Gloves - to protect your hands from sharp metal edges and possible contamination with oil or dust.
- 📸 Smartphone with camera - to photograph the wiring diagram before disconnecting them.
It is also important to purchase it yourself in advance thermostat. They come in different types and lengths of capillary tube. For refrigerators Indesit temperature regulators of the TAM series (for example, TAM-133) or their imported analogues (Danfoss, K59) are most often used. When purchasing, be sure to pay attention to the length of the sensitive tube: if it is too short, you will not be able to position it correctly, and if it is too long, it will interfere and may be damaged during assembly.
Access to the thermostat in different Indesit models
The design of refrigerators Indesit may vary depending on the year of manufacture and series. Accordingly, access to the thermostat is carried out in different ways. In most classic models with a top freezer, the thermostat is located inside the refrigerator compartment. However, the location of its attachment may vary: sometimes it is hidden under the lampshade, and sometimes behind a decorative strip.
Let's consider the main location options:
- 🏠 Option 1: Under the lamp shade. This is the most common scheme. The lighting lamp and thermostat are located in one plastic case in the upper part of the refrigerator compartment.
- 🏠 Option 2: Behind the decorative cover. In some models, the regulator handle is located on the front panel, and the mechanism itself is hidden behind a plastic cover inside the chamber.
- 🏠 Option 3: Outside the case. In older models, the thermostat may be located outside, on the top of the refrigerator, next to the quick freeze button.
If in your case access is through the lampshade, you will need to carefully remove it. It is usually held in place by latches or one or two screws. Be extremely careful: the plastic in old refrigerators becomes brittle and can crack if handled carelessly. If the screws are hidden by decorative plugs, they must be carefully pryed out with a thin knife. After removing the lampshade, you will have access to the electrical part and thermal sensor.
⚠️ Attention: The design of plastic elements may vary slightly depending on the specific modification of the refrigerator. If there are no screws, look for hidden latches, but do not use excessive force so as not to break the fasteners.
Step-by-step instructions for dismantling
After you have provided access to the insides of the unit, you can proceed directly to removing the faulty element. This stage requires care, as it is important not to damage adjacent nodes and to correctly remember the order of connecting the wires. Any error in switching can lead to incorrect operation of the refrigerator or even failure of the compressor.
Follow the following procedure:
- Unscrew the screws securing the thermostat housing to the wall of the refrigerator or plastic panel. Usually there are two or four of them.
- Carefully disconnect the plastic terminals with wires. To do this, it is best to use pliers, grabbing the terminal itself, and not the wire, so as not to break the wires.
- Remove the temperature control knob. It is simply pulled onto the rod and removed with light force.
- Bend the metal plate that presses the bellows tube to the evaporator. This tube is very thin and susceptible to damage.
- Carefully pull the tube out of its seat. If it is stuck or dirty, do not pull sharply so as not to damage it.
☑️ Dismantling checklist
After removing the old thermostat, it is recommended to compare it with the new one. Make sure that the capillary tube length, diameter and contact location are the same. If the new sensor has a longer tube, its excess can be carefully twisted into a ring, but under no circumstances should it be bent or cut. Damage to the tube will lead to freon leaking from the bellows, and the thermostat will stop responding to temperature changes, becoming a useless piece of metal.
Installing a new thermostat
Installing a new one thermostat is done in the reverse order. The main difficulty here is the correct placement of the sensitive tube. It should fit tightly to the surface of the evaporator in a specially designated place, often secured with a metal clamping strip. It is through this bar that the temperature is transferred from the evaporator to the gas-filled flask inside the tube, causing it to contract or expand.
When connecting the wires, be guided by the photographs taken earlier. The color marking of the wires may vary from batch to batch, so visual consistency of the wiring diagram is more important than the color of the insulation. Usually the wires are connected to the corresponding terminals: one goes to the compressor, the other to the network or lamp. Make sure the terminals are tight and not loose. Poor contact will lead to sparking, heating and possible melting of the plastic.
After connecting all the wires and fixing the tube, install the thermostat housing in place and tighten the screws. Put on the adjustment knob. This completes the mechanical part of the replacement. However, it is too early to rush to plug in the refrigerator. It is necessary to visually inspect the assembled structure for the absence of unnecessary parts or forgotten tools inside the chamber.
What will happen if the wires are connected incorrectly?
If the wires are mixed up, the refrigerator may not turn on at all, or the compressor will work continuously without turning off when the desired temperature is reached. In the worst case, a short circuit is possible immediately after connecting to the network.
Checking functionality and setting
The final stage is testing. Plug in the refrigerator. After a few seconds (or minutes, depending on the model), you should hear a click and the compressor will start. Let the unit run idle (without food) for 1-2 hours. During this time, it should gain temperature and turn off. If the compressor runs without a break for more than 2 hours and does not click, perhaps the thermostat does not sense the cold (poor tube contact) or the new device itself is faulty.
To adjust the temperature, use the regulator knob. In refrigerators Indesit the scale usually goes from 1 to 5 or from Min to Max. The optimal position for everyday work is the middle value. If you set the maximum cold, the compressor will run longer, consuming more electricity, and food near the rear wall may freeze.
Below is a table with approximate values for the thermostat settings:
| Knob position | Temperature mode | Recommendation |
|---|---|---|
| Min / 1 | +8...+10°C | For short-term storage, energy saving |
| Average / 3 | +4...+6°C | Optimal mode for daily use |
| Max / 5 | +2...+4°C | For quick freezing or hot weather |
| Off / 0 | - | The unit is turned off, the compressor does not work |
Frequently asked questions and possible problems
Even if you strictly follow the instructions, nuances may arise that confuse the home craftsman. Often questions concern the compatibility of parts or the behavior of the refrigerator immediately after replacement. For example, many users are afraid that after replacing the thermostat, the refrigerator began to freeze more or, conversely, less. This is often solved by simple adjustment.
If after replacement the compressor does not start at all, check for voltage at the thermostat input terminals. Perhaps the problem is not in the sensor, but in the start relay or the compressor itself, and you replaced a working part. It is also worth checking the integrity of the wires going to the thermostat - when dismantling it is easy to damage the old insulation.
⚠️ Attention: If, after replacing the thermostat, the refrigerator begins to operate in cycles: it runs for 5 minutes, stands for 10 minutes, and so on, this is a sign that the thermostat tube is in poor contact with the evaporator or a sensor with an inappropriate temperature range is used.
In some cases, it may be necessary to adjust the screw under the seal on the thermostat itself, but doing this without special equipment and knowledge is not recommended. The factory setting is generally optimal for most operating conditions. If you encounter difficulties that cannot be resolved by double-checking the connection diagram, it is better to contact a professional technician.
Is it possible to use a thermostat from another model?
Theoretically, it is possible if the mounting dimensions, tube length and temperature response range are the same. However, it is better to use original spare parts or their complete analogues to avoid problems with setup.
How to understand that the thermostat is definitely faulty?
The most reliable way is to test with a multimeter. If, when the temperature of the sensitive tube changes (lowering it in cold water), the resistance does not change (remains infinite or zero), the device is faulty. Also a sign is the absence of a click when turning the knob.
Where to buy a thermostat for Indesit?
Spare parts can be purchased in specialized household appliance stores, electronics markets or ordered online. Look for the markings indicated on the body of the old device (for example, TAM-133, K59-L1102).
Do you need to defrost the refrigerator before replacing?
Full defrosting is not necessary if access to the thermostat is from above. However, if there is a lot of ice in the freezer, which interferes with operation or access to the evaporator tube, it is better to wait until it thaws so that water does not get on the electrical contacts.
Why does the refrigerator not turn off after replacement?
Possible reasons: the wires are connected incorrectly, the new thermostat itself is faulty (defective), the tube does not fit tightly to the evaporator or there is a freon leak in the system (which requires calling a technician for refilling).
Is it possible to temporarily short-circuit the thermostat wires?
Yes, this will allow the compressor to start bypassing the sensor, but the refrigerator will work continuously until you unplug it. This is an emergency measure to preserve food, but you cannot constantly operate the unit in this mode - the compressor will burn out.