An unexpected shutdown of the refrigerator or, conversely, its continuous operation without pauses often indicates a failure of one of the key elements of the temperature control system. Thermoregulator (or thermostat) is responsible for turning the compressor on and off, maintaining the set temperature conditions in the cells. If you notice that the food in the freezer begins to melt, and ice appears on the shelves of the main compartment, or the motor hums around the clock without going into standby mode, most likely the problem lies in this sensor.
Equipment owners Atlant often face the need to replace this part, since Over time, the contacts inside the mechanism oxidize or “stick”, and the bellows tube loses its tightness. Fortunately, the design of these refrigerators allows you to carry out do-it-yourself repairwithout contacting a service center. This will not only save the budget, but also restore self-confidence.
However, before you start disassembling, you need to make sure of the diagnosis. Sometimes symptoms similar to a broken thermostat may indicate a freon leak or a faulty start relay. In this article, we will analyze in detail the diagnostic process, selecting a new spare part and a step-by-step replacement procedure so that your refrigerator works like new again.
Diagnostics of a thermostat malfunction
Before buying a new part, you need to exclude other possible causes of incorrect operation of the unit. Thermostat is a mechanical or electronic device that closes and opens the electrical circuit depending on the temperature of the evaporator. If the refrigerator does not turn on at all, but the light inside is on, this may be a sign of an open circuit in the regulator itself.
There is a simple way to check that does not require complex equipment. Open the refrigerator door and find the temperature control. Try turning its handle counterclockwise until it clicks. If there is no click and the motor is silent, perhaps the contacts inside are no longer closing. You can also conduct a test with a forced short circuit: if, when connecting the wires coming from the thermostat, the compressor starts, then the problem is definitely in the sensor.
⚠️ Attention: Carry out any manipulations with electrical wires and components of the refrigerator only with the power completely disconnected from the network! Failure to comply with safety precautions can lead to electric shock.
Another sign of a malfunction is continuous operation of the compressor. If the motor hums without stopping, and everything in the refrigerator compartment freezes, and the thermostat does not respond to turns of the handle, it means that its contacts are “stuck” in a closed state. In such cases replacing the thermostat is the only effective solution.
Choosing the appropriate thermostat model for Atlant
Refrigerators Atlant are equipped with various types of thermostats depending on the year of manufacture and the specific model. The most common mechanical thermostats have a capillary tube that is attached to the evaporator. It is important to choose an analogue with identical characteristics, otherwise the temperature regime will be violated.
When choosing a spare part, pay attention to the following parameters:
- 📏 Length of the capillary tube: it can vary from 0.6 to 2.5 meters. A tube that is too long can be carefully rolled up, but a short one cannot be extended.
- 🔌 Type of contacts and location: the terminals can be located on the top, side or bottom of the housing. Check if the connection diagram matches.
- ❄️ Temperature range: for single-compressor models and two-chamber systems, different types of sensors are required (for example, TAM-133 or TAM-145).
Often on the body old thermostat you can find markings, for example, TAM-133 or K-59. These notations will help you find an exact analogue. If the marking has been erased, it is better to remove the old part and visually compare it with the new one in the store, paying attention to the shape of the body and the length of the rod.
Is it possible to use a universal thermostat?
Universal thermostats (for example, with variable tube length) exist, but their installation requires more accuracy. You will have to cut off the excess part of the tube yourself and re-crimp the tip, which requires special tools and skills. For beginners, it is better to buy an original spare part or a complete analogue.
Necessary tools and preparation for work
To successfully replace the thermostat, you do not need a complex professional tool. All the necessary kit can be found in the drawer of most home craftsmen. The main thing is to prepare the workplace and provide good lighting, since some components in the refrigerator Atlant may be hidden.
You will need:
- 🔧 Screwdrivers: cross and flat (of different sizes) for removing panels and terminals.
- 🔪 Knife or side cutters: for neat cutting of insulation or plastic clamps.
- 🧤 Gloves: to avoid cutting yourself on the sharp edges of metal panels and not getting your hands dirty.
- 📸 Smartphone: to photograph the wiring diagram before dismantling.
Defreeze the refrigerator in advance. Although a complete defrost is not always necessary to replace the thermostat, the presence of water and ice can make access to the back wall and evaporator difficult. Leave the doors open for at least 2-3 hours so that the moisture completely evaporates.
☑️ Ready for repair
Removing the old thermostat
The process of removing the thermostat depends on where it is located in your models Atlant. In most modern models, the regulator handle is located inside the refrigerator compartment on the right wall or on the ceiling. In some older models, access to the mechanism is through the top panel or visor above the door.
If the handle is inside:
- Carefully remove the temperature control knob. It can simply pull towards itself or be held on a screw hidden under a decorative plug.
- Unscrew the screws securing the plastic thermostat housing to the wall of the refrigerator.
- Remove the protective cover to gain access to the electrical contacts.
Now the most important thing - work s capillary tube. It is very thin and easily damaged. It should not be bent at an acute angle or pulled with force. The tube passes through a hole in the chamber wall and is attached to the evaporator. Carefully disconnect the wire terminals, first remembering their location. Then carefully pull the tube out of its seat.
⚠️ Attention: The capillary tube is filled with freon under pressure. If damaged, gas will escape and the thermostat will become inoperative. Proceed without sudden movements.
Installation of a new thermostat and connection diagram
Installation of a new part is carried out in the reverse order of dismantling. First you need to secure the capillary tube. Insert it into the hole as far as it will go, being careful. The length of the protruding part must correspond to the original so that the sensor correctly reads the temperature of the evaporator.
Next is the electrical connection. It is critical here not to mix up the wires. Usually there are three of them:
- ⚡ Phase wire: comes from the network (often white or brown).
- 🔄 Wire to the compressor: goes to the start relay (often black or blue).
- 💡 Wire to the light bulb: goes to the lighting (often yellow or green).
In some models Atlant there may be only two wires if the backlight control is implemented separately. Use the photo you took earlier to make the correct connection. Secure the wires in the terminals tightly to avoid sparking and heating of the contacts.
After connection electricians, install the thermostat housing in place and secure it with screws. Put on the adjustment knob. Make sure that nothing prevents the door from closing and that the tube is not pinched.
Setting up and checking the operation of the refrigerator
After assembly, you need to check the functionality of the system. Plug in the refrigerator. In the first minutes you should hear a characteristic click - this is the closing of the thermostat contacts, starting the compressor. If the motor starts working, it means that the electrical part is connected correctly.
Now you need to adjust the temperature. Set the regulator knob to the middle position (usually this is a number 3 or 4). Let the refrigerator run for several hours. Check the temperature in the main chamber using a household thermometer. It should be within the limits +2...+5°C.
If the refrigerator turns off too early and does not get cold, or works without interruption, additional adjustment may be required. Some thermostats have adjustment screws under the seal, but for household repairs Atlant usually correct installation of the handle is sufficient. If the problem persists, the new thermostat may be defective or does not fit the specifications.
Typical errors and fault table
When doing independent repairs, even experienced craftsmen can make mistakes. Most often they are associated with careless handling of the capillary tube or incorrect connection of the wires. Below is a table that will help compare symptoms and possible causes.
| Symptom | Possible cause | Solution |
|---|---|---|
| The refrigerator does not turn on, the lamp is on | Open circuit in the thermostat | Replacing the thermostat |
| The motor runs without stopping | Contacts are “stuck” or freon is leaking | Checking the thermostat and freon pressure |
| Frequent on/off | Incorrect setting or loosening of the tube | Adjusting the handle, checking the tube fastening |
| Sparking in the area of the thermostat | Poor contact in the terminals | Tighten the screws terminals, clean the contacts |
One of the common mistakes is an attempt to “reanimate” an old thermostat by tapping or heating. Mechanical thermostats are not subject to repair, their internal structure is sealed and calibrated at the factory. Attempts to intervene will only speed up the final failure.
Also, do not ignore the condition of the door seal. If it does not fit tightly, warm air will enter the chamber, and the thermostat will constantly keep the compressor on, which will ultimately lead to its overload. Make sure that the door closes tightly.
Why is the new thermostat humming?
Sometimes after replacement, owners hear a quiet crackling or buzzing sound in the area of the regulator knob. This is normal for some models of mechanical thermostats (especially the TAM series) and is caused by the operation of the bimetallic strip inside. If there are no sparks or a burning smell, this is not a defect.
Frequently asked questions (FAQ)
Is it possible to temporarily short-circuit the thermostat wires to make the refrigerator work?
Technically, you can close the wires and the compressor will start. However, in this case, the refrigerator will run continuously until you manually break the circuit. This will lead to overfreezing of food, the formation of an ice coat and, ultimately, to overheating and breakdown of the compressor. Use this method only for short-term diagnostics.
What is the difference between the TAM-133 thermostat and TAM-145?
The main difference is the length of the capillary tube and the temperature range of operation. TAM-133 more often used in single-chamber refrigerators or freezers, a TAM-145 —in two-chamber models with a weeping evaporator. Installing an unsuitable model will lead to incorrect operation of the temperature regime.
How long does the thermostat in the Atlant refrigerator last?
The average service life of a high-quality thermostat is 5-7 active years use. However, with frequent power surges in the network or sudden temperature changes (frequent opening of the door), the service life can be reduced to 3-4 years.
Do you need to call a technician for replacement or can you do it yourself?
If you have basic skills in working with a screwdriver and an understanding of the principles of electrical safety, replacing a thermostat is one of the most accessible procedures to do it yourself. It does not require evacuation of the system or working with freon, since it only affects the electrical control circuit.