Refrigeration equipment of the brand Atlant is deservedly popular due to its reliability and ease of maintenance. However, any, even the highest quality mechanism requires attention over time, and often owners are faced with the need to understand exactly how the temperature control system functions. Thermoregulator in this system it plays the role of the main guardian of the climate inside the chambers, ensuring the safety of products and the correct operation of the compressor.
In this article we will analyze in detail the physics of the processes occurring inside your refrigerator and explain why precise tuning of this unit is critically important. You will learn how to distinguish a sensor failure from a compressor malfunction, and get answers to questions that often baffle inexperienced users. Understanding these principles will help you avoid unnecessary calls to a technician in simple situations.
Many people perceive the refrigerator as a “black box,” but knowledge of the basic principles of thermoregulation allows you to save energy and extend the life of the unit. The critical point is the fact that most breakdowns of Atlant thermostats are not associated with manufacturing defects, but with a violation of the tightness of the bellows or oxidation of contacts due to power surges in the network. Let's dive into the technical essence of the issue so that you can confidently diagnose the condition of your equipment.
The principle of operation of the thermostat in Atlant refrigerators
The basis of the temperature control system in most models Atlant is mechanical thermostat, the operation of which is based on the physical properties of gases and liquids. Inside the sensing element, called a bellows, there is a substance with a high coefficient of thermal expansion. When the temperature in the chamber rises, this substance expands, increasing the pressure inside the bellows.
This pressure is transmitted to a system of levers, which at a certain moment open or close electrical contacts. This is how the start or stop command is given. compressor. This process is cyclical and continuous: as soon as the chamber becomes cold enough, the pressure drops, the contacts open, and the motor stops until the next heating cycle.
It is important to understand that the accuracy of operation depends on many factors, including the tightness of the contact capillary tube to the evaporator. If the tube is displaced or not pressed tightly enough, the sensor will read the wrong temperature, which will lead to frequent switching on or, conversely, to defrosting of food. Modern models may use electronic resistance sensors, but mechanics remain dominant in the budget and mid-range segment.
There are several types of thermostats installed on equipment Atlant, and they are not always interchangeable without modifications. The differences relate to the length of the capillary tube, the temperature range of operation and the presence of additional contacts for indication.
- 🔹 Single-contact thermostats — used in simple models without the No Frost system, they only control the activation of the motor.
- 🔹 Two-contact thermostats —have an additional contact for turning on the overload indication light or alarm signal.
- 🔹 Thermostats with an air damper - found in two-chamber models, they regulate the flow of cold air between the chambers.
Technical detail
why does the thermostat click?: When the contacts open or close, a micro-spark occurs inside the thermostat. In some models, especially the older Atlant series, this sound can be quite loud and audible even from the next room. This is a normal operating process, and not a sign of a malfunction, if a click occurs when the compressor is turned on or off.
Design and main elements of the regulator
To effectively diagnose or replace, you need to clearly understand what it consists of thermostat. The device is a sealed unit, usually enclosed in a plastic or metal case, from which extends a long thin tube called a capillary. At the end of this tube there is a sensitive element, which is placed in the cooling zone.
Inside the housing there is a contact group made of silver or its alloys to ensure better conductivity and resistance to sparking. A lever system connects the bellows to the moving contact. On the outside of the housing there is usually a shaft with an adjustment knob that allows the user to change the spring tension, thereby adjusting the response temperature.
⚠️ Attention: It is strictly forbidden to open the sealed thermostat housing or try to repair its mechanisms. Violation of the tightness of the bellows will lead to an immediate loss of functionality of the unit, since the working substance will evaporate.
The length of the capillary tube is an important parameter that varies depending on the model of the refrigerator Atlant. Standard values can range from 0.6 to 1.3 meters. When replacing a part with an analogue, you must take this size into account: if the tube is too short, you simply will not be able to install the sensor in its normal place; if it is too long, you will have to carefully twist the excess, making sure not to pinch the tube.
In addition, markings may be applied to the body indicating the temperature range. For example, the mark -24...-16 means that the contacts open when the temperature reaches from minus 24 to minus 16 degrees Celsius. For the refrigeration chamber, these values will be positive, usually in the range from +4 to +12 degrees.
The table below shows the common types of thermostats used in technology Atlantand their main characteristics:
| Thermostat type | Capillary length | Temperature conditions | Application |
|---|---|---|---|
| TAM-112 | 0.73 m | Refrigerator compartment | Single-chamber models |
| TAM-125 | 1.3 m | Freezer compartment | Two-chamber models |
| TAM-133 | 0.75 m | Refrigerator compartment | Models with one compressor |
| K-59 | 0.75 m | Universal | Analogue for most models |
Symptoms of a malfunctioning thermostat
How to understand that the problem lies in the temperature controller, and not in the compressor or freon leak? There are a number of characteristic signs that should alert the owner. Most often, the first “bell” is a change in the operating mode of the refrigerator: it starts to freeze too much or, conversely, stops gaining temperature.
If your Atlant works non-stop, hums around the clock and a huge “fur coat” freezes on the back wall, this is a sure sign that the thermostat contacts are “stuck” in the closed position. The compressor receives power constantly and does not turn off, which leads to overheating of the motor and increased energy consumption.
The opposite situation - the refrigerator is silent. You plug it in, the light comes on, but the engine does not start. If you turn the control knob at the same time, you hear a quiet click, but the motor does not start; perhaps the contacts have oxidized or are completely destroyed. In this case, the circuit does not close and the start command is not received.
It is also worth paying attention to the condition of the products. If everything is melting in the refrigerator compartment, and there is ice in the freezer, or vice versa - the vegetables are frozen into stones, this indicates incorrect operation thermal sensor. It either does not feel real cold, or ignores the signal that the desired temperature has been reached.
- ❄️ Continuous operation: The compressor hums without interruption, ice is freezing.
- 🔇 No response: The refrigerator does not turn on, although the light is on and there is voltage in the socket.
- 🌡️ Chaotic cycles: Too frequent switching on and off (clocking), which does not have time to stabilize the temperature.
Diagnostics and performance testing
Before going to the store for a new part, you need to make sure that malfunction of the old regulator. To carry out diagnostics, you will need a minimum set of tools: a screwdriver, pliers and, preferably, a multimeter to “test” the circuit. Do not forget about safety precautions - all work is carried out only with the power supply disconnected!
The first stage is a visual inspection and access to the thermostat. In refrigerators Atlant it is usually located inside the refrigerator compartment on the side wall or under the top cover, or in the engine compartment below, depending on the model. Carefully remove the regulator knob and the protective panel.
If you do not have a multimeter, you can use the exclusion method. Disconnect the wires from the thermostat and connect them together directly (using an insulated jumper or simply twisting them together if the design allows). If, after connecting to the network, the refrigerator starts working and gets cold, then the problem is 100% in the regulator. If the motor does not start even with the contacts closed, you need to look for the cause in the start relay, compressor or wiring.
⚠️ Attention: When connecting the wires directly to check, do not leave the refrigerator in this state for a long time. This is an emergency operation mode, and without temperature control, the compressor may burn out from overload or the products will spoil from hypothermia.
When using a multimeter, switch the device to resistance measurement mode (Ohms). At room temperature, the contacts of a conventional refrigeration thermostat should be closed (resistance close to zero). If the device shows a break (one or infinity), the part is faulty. Also check that there is no breakdown on the case - the resistance between the contacts and the metal case should be infinite.
☑️ Thermostat diagnostics
Step-by-step instructions for replacing the regulator
Replacing the thermostat in the refrigerator Atlant - procedure, accessible to a home craftsman with basic skills, but it requires care and attention. The main rule: do not damage the capillary tube of the new sensor, since this is the thinnest element, the violation of the tightness of which is fatal.
Start by purchasing the correct analogue. It is best to look for an original spare part by the catalog number indicated on the body of the old part. If the original is not available, select an analogue with similar temperature characteristics and capillary length. Before installing a new regulator, let it sit at room temperature for several hours if it was brought in from the cold.
The process of dismantling the old thermostat requires caution. Disconnect the wires by remembering or photographing their locations (they are usually labeled or color-coded). Then carefully pull the capillary tube out of its seat. In some models Atlant it can be glued or fixed with clips that need to be carefully snapped off.
Installation of the new element is done in the reverse order. Insert the sensing element into the standard hole as far as it will go, making sure that it fits snugly against the evaporator wall. Secure the tube with standard clamps. Connect the wires according to the diagram, check the reliability of the connections. After assembling the case, turn on the refrigerator and check the first cycle of operation.
Setting and calibrating the temperature
After replacing the regulator or scheduled defrosting, it is often necessary to adjust the temperature regime. On the refrigerator thermostat knob Atlant there is usually a scale from 1 to 7 (or Min/Max). It is important to understand that the numbers do not mean degrees Celsius, but indicate the intensity of cooling.
The position “1” or “Min” corresponds to the highest temperature (the least cooling), and the position “7” or “Max” corresponds to the most severe frost. For normal operation, in most cases it is recommended to set the knob to the middle position, for example, to number 3 or 4. This provides an optimal balance between food safety and compressor load.
If you notice that the food in the refrigerator compartment begins to freeze at the back wall, reduce the value on the regulator. If the refrigerator “does not hold” cold and the food spoils, add power. Remember that changing the setting entails changing the duration of the compressor operating cycles.
In two-chamber models with one compressor, the adjustment most often affects the refrigerator compartment, while in the freezer the temperature depends on the settings of the main circuit. In models with a system No Frost and electronic control, calibration can be carried out through the service menu, but this already requires the qualifications of an engineer.
Why does the Atlant refrigerator not turn off after replacing the thermostat?
If after replacing the regulator the refrigerator works without stopping, there may be several reasons. First, the thermostat may have been installed with the wrong temperature range (cut-out temperature too low). Secondly, the sensing element may not be installed tightly to the evaporator, which is why it does not sense real cold. Thirdly, a freon leak is possible, and the refrigerator simply cannot reach the desired temperature, so the thermostat does not open the contacts.
Is it possible to use a thermostat from another brand?
Yes, you can, if the main parameters match: the length of the capillary tube, the diameter of the thread and the operating temperature. Often, instead of native Belarusian TAM thermostats, Italian analogues of Ranco or Danfoss (now Secop) are successfully installed. The main thing is to make sure that the contacts and seats match, or be prepared to slightly adapt the mount.
How often should you change the thermostat?
The service life of a high-quality thermostat is on average 5-7 years, which corresponds to the average life of other refrigerator components. However, with frequent power surges in the network or regular overloads (opening doors, installing hot products), it may fail earlier. Planned replacement is not required, they are replaced only when a breakdown occurs.
What to do if the regulator knob is broken?
If only the plastic switch knob is broken, and the mechanism itself is working, it is not necessary to change the entire thermostat. The handle can be found in parts stores as a separate part, or you can temporarily use pliers to rotate the stem (carefully!). However, operation without a handle is inconvenient, since it is impossible to quickly adjust the mode.