Reduced cooling efficiency, formation of ice Crusts or, conversely, a complete stoppage of the compressor often indicate a malfunction of the temperature control system. In refrigerators of the Belarusian brand Atlant a thermostat is responsible for these processes, which opens or closes the electrical circuit depending on the temperature in the chamber. If you find that the equipment has stopped turning off or on, most likely you will need to replace this unit.
Replacing the thermostat yourself is a completely solvable task for a person with minimal skills in working with electrical appliances, but it requires strict adherence to safety precautions and an understanding of the electrical circuit. Incorrect connection of wires can lead to compressor failure or even fire. Therefore, before starting work, you must carefully study the contact markings and the sequence of actions described in this manual.
In this article we will analyze in detail the process of dismantling the old sensor and installing a new one, paying special attention to the nuances of connecting wires of different colors. You will learn how to choose the right replacement if the original spare part is not on sale, and what mistakes self-taught craftsmen most often make. Carefully reading the instructions will help you avoid costly mistakes and restore the functionality of the refrigerator.
Diagnostics of the malfunction and preparation for repair
Before disassembling the refrigerator, 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. The main sign of a thermostat failure is a situation where the compressor either runs continuously without turning off, or is silent, despite the fact that the chamber is warm. For accurate diagnostics, it is often necessary to “ring” the contacts of the device with a multimeter in different temperature conditions.
If you have decided to replace, the first step will be to disconnect the refrigerator Atlant from the power supply. This is a critical safety step: any manipulation of live electrical components is strictly prohibited. After this, you should empty the refrigerator compartment of food, remove shelves and drawers to provide free access to the back wall or ceiling, where the evaporator and thermostat are usually located.
To carry out the work you will need a minimum set of tools. It is important to prepare them in advance so as not to interrupt the process of searching for the desired item.
- 🔧 Screwdrivers: Phillips and flathead (of different sizes for removing panels).
- 🔪 Knife or flat spatula for carefully removing plastic plugs.
- 🔌 Pliers or side cutters (for working with wires, if necessary).
- 📏 Multimeter (for checking circuit integrity and diagnostics).
⚠️ Attention: Before starting disassembly, make sure that there is no ice in the chamber, which could damage the capillary tube of the new thermostat if moved carelessly. Defrosting the refrigerator is a mandatory stage of preparation.
Removing the old thermostat
In refrigerators Atlant the thermostat is most often located inside the refrigeration chamber. Access to it can be organized in different ways: in some models it is hidden behind a plastic cover on the ceiling of the chamber, in others it is located in a niche above the door or behind a decorative strip. First, you need to carefully remove the temperature control knob if it protrudes outward, simply pulling it towards you.
Next, you should unscrew the fastening screws that hold the protective casing or lampshade, under which the thermostat housing is hidden. Be careful with plastic latches: they can be fragile, especially if the refrigerator has been in use for a long time. After removing the cover, you will see the thermostat itself, the capillary tube going into the evaporator, and the block with connected wires.
The removal process requires care so as not to damage the capillary. The tube should not be bent at an acute angle or pulled with force.
- 📸 Take a photo of the location of the wires before disconnecting - this will help you avoid getting confused during assembly.
- 🏷️ Mark the wires with a marker or electrical tape according to the contacts on the terminals.
- ❄️ Carefully remove the capillary tube from the hole in the chamber wall, straightening it.
Nuances of attaching the capillary tube
The capillary tube in older models can be glued to the evaporator. Do not tear it off by force - use a hair dryer to soften the glue or ice, otherwise there is a risk of damaging the thin copper tube, which will lead to freon leakage.
After freeing the tube, unscrew the nut securing the thermostat to the chamber wall and remove the device. Now you need to disconnect the wires. In some cases they may be twisted and insulated, in others they may be connected through a connector. If the wires are oxidized, they are cleaned until shiny. The old thermostat is disposed of, since these components, as a rule, cannot be repaired.
Selecting a suitable replacement part
Selecting an analogue is a critical stage on which the correct operation of the refrigerator depends. Atlant. Thermostats differ in the length of the capillary tube, operating temperature range, the presence or absence of a forced defrost button, and the size of the housing. Using an unsuitable model can result in the refrigerator either undercooling food or “overfreezing” them, turning vegetables into ice.
Original thermostats for Atlant are often marked TAM (Thermostat Automatic Freezer) or K (Terminal). The most common models are TAM-133, TAM-145, K-59, K-57. When purchasing, pay attention to the length of the capillary tube: if the new tube is longer than the old one, its excess can be carefully rolled into a ring inside the case, but under no circumstances should it be cut or pinched.
Below is a table of correspondence of popular thermostat models used in refrigerators of this brand:
| Original / Analog | Capillary tube length | Contact type | Application features |
|---|---|---|---|
| TAM-133 (K-59) | 0.75 m - 2.5 m | 3 contacts | Single-chamber and double-chamber models |
| TAM-145 | 0.75 m - 3.0 m | 2 contacts | Freezers, no defrosting |
| K-57 (L=2.5m) | 2.5 meters | 3 contacts | For models with the No Frost system (rarely) |
| TAM-112 | 0.75 m | 2 contacts | Small refrigerators, old models |
When purchasing in a store, be sure to check with the seller for compatibility with your refrigerator model. The presence of a defrost button (usually a fourth contact or a separate mechanism on the body) is important for models where the evaporator defrosts manually or semi-automatically. The absence of this function where it is needed will lead to the evaporator becoming overgrown with ice.
Connection diagram and wire marking
The most crucial moment is connecting the electrical wires to the new thermostat. In refrigerators Atlant the color coding of wires is usually standard, but there may be exceptions depending on the year of manufacture. The classic circuit for a three-pin thermostat (with a defrost button) looks like this: the red wire goes to the compressor, the black wire goes to the defrost button, the white (or yellow/green) wire goes to the lamp and button.
If your thermostat has two contacts, the circuit is simplified: one wire is phase (incoming), the second goes to the compressor. It is important to understand that the thermostat breaks the phase. By mixing up the wires, you can leave the refrigerator without light or, worse, short out the circuit. Before connecting, make sure that the wire insulation is intact. If the wires are short, they need to be extended using terminal blocks or high-quality soldering followed by heat shrink insulation.
Basic rules for connecting wires:
- 🔴 The red wire is usually connected to a contact that closes when the temperature drops (to the compressor).
- ⚫ The black or brown wire often goes to the defrost circuit or the second relay contact.
- ⚪ The white or yellow-green wire is responsible for the lighting circuit (lamp in the chamber).
⚠️ Attention: Color markings may vary depending on the year of manufacture of the refrigerator. Always check the electrical diagram pasted on the back wall of the unit, or use a multimeter to check the continuity of the circuit.
☑️ Check before turning on
For connections, use only high-quality materials. Twists, even carefully insulated with electrical tape, oxidize and heat up over time. The best option is to use terminal blocks or tin soldering. After connecting, visually check all connections again for the absence of protruding copper hairs that could cause a short circuit.
Installation of a new thermostat and assembly
After successfully connecting the wires, you need to install the thermostat housing in its original place. The capillary tube should be inserted into the hole in the chamber wall very carefully, trying not to damage its thin walls. The depth of immersion of the sensitive element (the can at the end of the tube) must comply with the requirements of the instructions - usually 30-40 mm inside the evaporator heat exchanger.
Secure the thermostat with a nut or screws, ensuring that the housing is tightly pressed to the wall, but without excessive force, so as not to crack the plastic. If the design provides for pressing the capillary with a metal strip to the evaporator, install it in place. This is necessary for accurate temperature transfer from the evaporator to the sensor.
The following is the reassembly process:
- Install the lampshade and screw it in place.
- Place the temperature adjustment knob onto the thermostat rod.
- Close the decorative panels and plugs.
- Check that nothing is preventing the refrigerator door from closing.
Only after complete mechanical assembly can you begin electrical tests. Make sure the chamber is dry and no tools are left inside. Plug in the refrigerator. In the first minutes of operation, listen to how the compressor starts: the sound should be smooth, without strong vibrations or humming.
Setting up and testing operation
After turning on, set the thermostat knob to the middle position (usually number 3 or 4). Let the refrigerator run for at least 30-40 minutes. During this time, it should gain temperature and, depending on the settings, either continue working or shut down. If the compressor runs continuously for more than an hour and the temperature in the chamber drops below zero (food freezes), the thermostat may require adjustment.
Many thermostats have adjusting screws on the housing that are covered with a seal or paint. By turning the “Cold” screw you can change the shutdown range, and by turning the “Diff” screw you can change the difference between the on and off temperatures. However, it is not recommended to touch them without special equipment and experience, as you can reset the factory settings.
Signs of correct installation of the thermostat:
- ✅ The compressor turns on and off cyclically.
- ✅ The temperature in the main chamber is kept within the limits +2...+5°C.
- ✅ The lighting lamp lights up when the door is opened.
If the Atlant refrigerator behaves strangely after replacing the thermostat (it often turns on, does not freeze completely), perhaps the problem is not only in the sensor, but also in a freon leak or contamination of the condenser. In this case, simply replacing the thermostat will not solve the problem completely.
Frequently asked questions (FAQ)
Is it possible to install a thermostat from another manufacturer, for example, Danfoss or Ranco?
Yes, you can. Danfoss (K series) and Ranco thermostats are world standards and are often used as direct analogues for refrigerators Atlant. The main thing is to ensure compliance with the dimensions, length of the capillary tube and type of contacts (with or without a defrost button).
Why does the new thermostat click, but the refrigerator does not turn on?
This may indicate a malfunction of the compressor start relay or the motor itself. The thermostat gives a proper signal (click), but the circuit does not close further. It is also worth checking the integrity of the wires going from the thermostat to the compressor.
Is it necessary to defrost the refrigerator before replacing the thermostat?
Yes, definitely. Ice on the evaporator can damage the capillary tube of the new sensor during installation and also make access to the fasteners difficult. Complete defrosting will take from 8 to 24 hours.
What to do if the capillary tube of the new thermostat is too long?
It is strictly forbidden to cut the capillary tube - this will break the tightness of the system and lead to leakage of sensitive liquid. The excess length must be carefully rolled into rings with a diameter of at least 3-4 cm and placed inside the refrigerator body or behind the back panel, avoiding kinks.
How to understand that the thermostat is faulty without a multimeter?
An indirect sign is that the refrigerator does not turn off at all or does not turn on when the knob is turned to maximum. You can also remove the thermostat, place its sensitive element in a container with warm water - you should hear a click of the contacts opening (if it was closed).