A sharp increase in temperature in the refrigerator compartment or, conversely, excessive freezing of the rear wall often indicates a failure of the thermostat. In two-chamber models Atlant this element is responsible for turning the compressor on and off, maintaining the set temperature. If you notice that the unit works without stopping or does not start at all, and the light inside is on, most likely the problem lies in the temperature sensor.
Replacing the thermostat yourself is a very real task for a home craftsman, which does not require complex specialized equipment. The main thing is to observe safety precautions and strictly follow the connection diagram, since an error in connecting the wires can lead to a short circuit or failure of the compressor. In this article we will analyze in detail the process of diagnosing, dismantling the old and installing a new temperature controller.
Before starting disassembly, you need to make sure that you have a working spare part. Thermostats for refrigerators Atlant may differ in the length of the capillary tube, mounting method and number of contacts. An incorrectly selected analog may not fit in size or work incorrectly, so checking the markings is a mandatory step in preparation for repairs.
Diagnostics of a thermostat malfunction
The first step should always be an accurate diagnosis. Failure to operate does not always indicate a breakdown of the thermostat itself; sometimes the problem lies in a freon leak or a faulty start relay. However, if the compressor hums but does not start, or works continuously without turning off for hours, suspicion falls precisely on thermostat. For the initial check, you can try to close the contacts on the sensor itself, having first disconnected the refrigerator from the power supply.
If after closing the contacts the compressor starts confidently, it means that the power circuit is intact, and the problem is really in the sensor. In models Atlant with electromechanical control, sticking of contacts inside the mechanism itself or loss of tightness of the bellows is often encountered. It is impossible to determine this visually; a test with a multimeter is required in different temperature conditions.
⚠️ Attention: Before starting any diagnostic and disassembly work, be sure to disconnect the refrigerator from the electrical network. Working with live electrical wiring is deadly.
For a more accurate check, remove the thermostat and place its sensitive capillary tube in a container of ice water for a few minutes. After cooling, ring the contacts: in a cold state they should be closed (for normally closed models) or open when heated. Lack of response to a change in temperature will indicate the need to replace the part.
Often owners confuse a malfunction of the thermostat with a breakdown of the defrost sensor, especially in No Frostsystems. It is important to understand that in refrigerators with a drip defrosting system, the thermostat controls only the compressor, while in models with automatic defrosting, a separate or electronic module may be responsible for the defrosting process. data-i="67">Preparation of tools and selection of spare parts Atlant with a drip defrosting system, the thermostat controls only the compressor, while in models with automatic defrosting, a separate one may be responsible for the defrosting process timer or electronic module.
Preparation of tools and selection of spare parts
For a successful replacement, you will need a minimum set of tools, which can be found in the arsenal of most men. The main requirement for the tool is serviceability and safety, since you will have to work with plastic elements and electrical contacts. Do not use damaged tools to avoid damaging the wire insulation or the fragile plastic of the case.
The list of required equipment includes:
- 🔧 Screwdrivers (Phillips and flathead) for removing panels and terminals.
- 🔌 Pliers or round-nose pliers for manipulating wires.
- 🌡️ Multimeter to check the continuity of the circuit.
- 🧤 Safety gloves to protect your hands from sharp edges.
Choosing a new thermostat is a critical moment. In refrigerators Atlant most often used are regulators of the brand K-59, TAM-133 or RTK. They may differ in the length of the capillary tube: for two-chamber models it is usually 0.73, 0.9 or 1.3 meters. If the tube is too long, it will have to be carefully laid inside the case; if it is short, the sensor will not read the temperature correctly.
Also pay attention to the number of contacts. A standard thermostat has three terminals, but sometimes there are two. If you install a three-pin sensor instead of a two-pin one, the third wire (usually yellow-green) can be left unconnected; it is responsible for indicating the operation of the compressor, which may not be provided in your model.
When purchasing, pay attention to the country of origin and certification. Cheap Chinese analogs may be unstable or have a wide temperature range, which will lead to food spoilage. Original spare parts Atlant or high-quality European analogues (Danfoss, Thermo) last much longer.
Removing the old thermostat
The process of removing the temperature sensor depends on the specific model of the refrigerator Atlant. In most cases, the thermostat is located inside the refrigerator compartment, hidden behind a plastic panel or in the lighting control unit. In some older models, it may be located outside, on the back wall of the unit.
Algorithm of actions for internal location:
- Empty the refrigerator compartment of food and remove the shelves to provide access to the top part.
- Find the plastic cover hiding thermostat and lighting lamp.
- Carefully pry off the cover with a flat screwdriver or knife, being careful not to damage the plastic latches.
- Unscrew the screws securing the thermostat housing, if any.
After removing the protective cover, you will see the sensor itself with a capillary tube extending from it. The tube is usually fixed in a special hole or pressed against the evaporator with a bar. It must be released very carefully, since if the thin copper is damaged, the refrigerant inside the bellows will come out, and the new sensor will immediately become inoperative.
☑️ Checklist before removing the wires
The next step is to disconnect the electrical wires. It is extremely important here not to confuse which wire was connected where. It's best to take some close-up photos or sketch out the diagram before disconnecting. Usually the wires are color-coded, but you should not rely on color alone, since previous technicians may have made changes to the wiring.
⚠️ Attention: The capillary tube of the thermostat is very thin and fragile. Do not bend it at an acute angle or pull sharply, otherwise the tightness of the system will be broken.
If the thermostat is located outside (on the back wall), the process is simplified: just remove the back cover of the refrigerator, find the round block with the regulator and remove the casing from it. Further actions are similar: disconnect the wires and remove the sensitive element from the evaporator.
Connection diagram and marking of wires
The most crucial moment is connecting a new thermostat. An error here could result in the refrigerator not starting, running non-stop, or causing a short circuit. The thermostat body usually has terminal markings: 3, 4, 6 or L, 1, 2, 4. Understanding this marking is the key to success.
The standard connection diagram for most models Atlant looks like this:
| Contact | Wire color (standard) | Purpose |
|---|---|---|
| 3 (or L) | Red / Brown | Power supply (Phase) |
| 4 (or 1) | Black / Orange | To compressor |
| 6 (or 2) | Yellow / Green | Operation indicator (lamp) |
It is important to note that wire colors may vary depending on the year of manufacture of the refrigerator. Therefore, you need to focus primarily on the operating logic: the wire coming from the network must be connected to the wire going to the compressor through the thermostat contacts. The third contact, if there is one, goes to the compressor operation indicator lamp.
When connecting, make sure that the contacts are tightly seated on the terminals. If the connectors are loose, you can gently tighten them with pliers, but without excessive force, so as not to break the plastic base. Poor contact will lead to sparking, heating and eventual burning of the terminal block.
In models with electronic control, replacing a mechanical thermostat with an electronic one or vice versa requires resoldering the wires and changing the operating logic, which only professionals can do. In this article, we are considering replacing with a similar mechanical thermostat thermostat.
Installing and configuring a new sensor
After connecting the wires, it is necessary to correctly install the capillary tube of the new thermostat. It should be located in the same place and with the same immersion depth as the old one. Typically, the tube is inserted into a hole in the evaporator or pressed with a special plate to its surface.
The seating depth of the tube affects the accuracy of temperature measurement. If you plant it too deep, the refrigerator will turn off prematurely and food may defrost. If it is too shallow, the unit will work longer than necessary, forming excess ice.
Fix the thermostat housing in its original place, making sure that nothing prevents the adjustment knob from turning. Reassemble the plastic panel in reverse order, securing all latches and screws. Make sure that the wires are not pinched by the case and do not touch moving parts (if there are any, for example, a fan).
The temperature is adjusted experimentally. Set the control knob to the middle position (usually number 3 or 4 out of 7). Start the refrigerator and let it run for a few hours. Check the temperature in the chamber using a household thermometer. If it is too low, reduce the value, if high, increase it.
For two-chamber refrigerators Atlant it is important to adjust the balance between the refrigerator and freezer compartments. The thermostat controls the temperature in only one chamber (usually the refrigerator), so the condition of the freezer will depend on the health of the system as a whole. The optimal temperature in the refrigerator compartment should be +2...+4°C, and in the freezer -18°C and below.
Check operation and typical errors
After assembly and first startup, carefully listen to the operation of the unit. The compressor should turn on immediately or after a short period of time (if there is protection against restarting). After some time, when the temperature in the chamber reaches the set value, the refrigerator should turn off. Work and rest cycles should be approximately equal (for example, 10 minutes work, 10-15 rest).
Typical mistakes that beginners make:
- ❌ Incorrect wire connection (phase and zero or compressor contacts are reversed).
- ❌ Damage capillary tube during installation.
- ❌ Insufficient depth of the sensitive element.
- ❌ Ignoring grounding (if it is provided for by the design).
If the refrigerator starts working continuously without turning off, perhaps the thermostat does not sense the cold. Check whether the tube fits tightly to the evaporator. If the unit does not turn on at all, check the connection diagram again and test the circuit with a multimeter. It is possible that the new sensor was also defective, which is rare, but still possible.
⚠️ Attention: If, after replacing the thermostat, the refrigerator makes strange sounds, hums louder than usual, or smells burning, immediately unplug it and contact a professional technician.
In some cases, after replacement The thermostat may take time to stabilize the temperature, especially if the refrigerator has been turned off for a long time. Do not try to immediately load the chamber with food; let the unit run idle for 2-3 hours.
Frequently asked questions (FAQ)
Is it possible to install a thermostat with a different marking, for example, instead of K-59 put TAM-133?
Yes, it is possible if the overall dimensions, mounting method and length match capillary tube. These models are complete analogues and have similar temperature characteristics. The main thing is to connect the wires correctly according to the diagram.
Why does the refrigerator turn on immediately after it is turned off?
This may indicate a malfunction of the new thermostat (sticking contacts) or that the sensitive tube is installed incorrectly and does not have time to cool. Also, the reason may be a freon leak, due to which the temperature does not drop and the sensor does not give a command to turn off.
Is it necessary to defrost the refrigerator before replacing the thermostat?
Complete defrosting is not necessary if you work quickly and carefully. However, if there is a lot of ice in the compartment, it is better to leave the refrigerator turned off for several hours to allow the ice to melt. This will make access to the evaporator easier and reduce the risk of damage to the thermostat tube.
Where can you find the thermostat markings in the Atlant refrigerator?
The markings are usually applied to the metal body of the thermostat itself or to its plastic base. To see it, you often have to partially dismantle the device. Also, information about the type of sensor can be in the service book or on a sticker inside the refrigerator compartment.
How long does a new thermostat last?
The average service life of a high-quality thermostat is 5-7 years or more. However, with frequent power surges or mechanical damage, this period may be shortened. Installing a voltage stabilizer will extend the life of not only the thermostat, but also the compressor.