Brand refrigerators Atlant are deservedly considered one of the most reliable and repairable models on the household appliances market. However, even the highest quality equipment breaks down over time, and one of the most common problems is a violation of the temperature regime, for which it is responsible thermostat. If your refrigerator stops turning off, works without interruption, or, conversely, stops freezing food, the reason often lies in this small but critically important unit. Replacing a part yourself is a real opportunity to save a significant amount, since the services of a technician can amount to up to 50% of the cost of a new spare part.
Before starting disassembly, you need to make sure the diagnosis is correct, since symptoms of a malfunctioning thermostat may be similar to problems with a compressor or refrigerant leak. Removing the thermostat requires some care and a basic set of tools, but does not require deep engineering knowledge. In this article we will analyze in detail all stages of work, from diagnostics to installation of a new element, paying special attention to the nuances of working with electrical wiring and capillary tube.
It is important to understand that ignoring signs of failure can lead to failure of more expensive components, for example, a motor-compressor that will operate on wear. In Atlant refrigerators with the No Frost system, the thermostat is often located behind the back wall of the freezer, which requires complete defrosting of the unit before starting work. A correctly completed replacement will return your device to factory operating parameters and extend its service life for many years.
Fault diagnosis thermostat
The first step in any repair is an accurate diagnosis to rule out other possible causes of the failure. If you notice that the refrigerator Atlant works almost non-stop, and the temperature in the chambers drops below normal (food in the refrigerator compartment freezes), this is a direct signal that the thermostat contacts are sticking. In this case, temperature controller does not send a signal to turn off the compressor, which leads to continuous operation of the system.
The opposite situation, when the unit does not turn on at all or turns on for a short time and turns off again, may also indicate a problem. In this case, the contacts may have oxidized or lost conductivity, and the electrical circuit does not close. For an initial check, you can try turning the regulator knob to its extreme positions, listening for a characteristic click, which indicates the mechanical serviceability of the switch.
- 🔍 The compressor works continuously, without turning off even when a low temperature is reached.
- ❄️ In the refrigerator compartment, food freezes, and excessive water forms in the freezer ice.
- 🔌 The refrigerator does not respond when plugged in or makes rare clicks without starting the motor.
There is a simple test method that is often used by craftsmen: removing the thermostat from the circuit. If, when connecting the contacts directly, the compressor starts and operates stably, then the problem is in the sensor. However, this method requires caution to avoid short circuiting or damaging the wiring.
⚠️ Attention: Direct shorting of contacts for testing is only permissible for a short time (no more than 15-20 minutes) for diagnostic purposes. Long-term operation of the refrigerator bypassing the thermostat will lead to freezing of the evaporator and overload of the compressor.
Necessary tools and preparation of the workplace
High-quality repairs are impossible without the right tools. To remove the thermostat on a refrigerator Atlant you do not need complex industrial equipment; a basic home DIY kit is enough. It is important that all tools are in good working order and at hand, since the process may require the simultaneous holding of several structural elements.
Particular attention should be paid to lighting the workplace, since the internal cavities of the refrigerator, especially in the area of the evaporator, are often shaded. You will need a good portable lamp or a powerful flashlight to clearly see the mounting locations and color coding of the wires.
☑️ Tools for replacing the thermostat
A multimeter is ideal for working with electrical contacts, allowing you to check the continuity and absence of short circuit. Also stock up on electrical tape or heat-shrink tubing to insulate the connections, which is a critical step for the safe operation of the electrical appliance.
Don't forget to prepare a container to collect melt water if your refrigerator is equipped with a system No Frost or if defrosting is required to access the unit. It is better to cover the floor at the work site with absorbent rags or polyethylene to avoid damage to the floor covering.
Removing the thermostat in refrigerators with a crying evaporator
In classic models Atlant with a drip defrosting system, the thermostat is usually located inside the refrigerator compartment. It is accessed through a plastic cover that hides the lighting lamp and regulator. Before starting work, be sure to disconnect the refrigerator from the electrical outlet by unplugging the plug from the socket.
Carefully remove the temperature control knob by pulling it towards you and dismantle the decorative panel. Below it you will see the thermostat housing, which is attached to the inner wall of the chamber or to the control panel. Unscrew the mounting screws holding the case and carefully remove the device out.
The key point is to work with capillary tube. This is a thin copper tube that goes deep into the housing and is in contact with the evaporator. It is very fragile, and its damage will lead to refrigerant leakage, which will make further repairs economically unfeasible.
- 🔧 Remove the plastic cover by unscrewing the screws or releasing the latches.
- 📏 Fix the position of the old tube so that the new one stood in the same place.
- 🔌 Disconnect the wire terminals, having previously photographed the connection diagram.
When removing the old thermostat, try not to pull the tube itself, but carefully push it through the hole, helping with your fingers from inside the chamber. The new element is installed in the reverse order, while the sensitive flask should fit tightly to the evaporator in the same place where the old one was located.
⚠️ Attention: The capillary tube of the thermostat is filled with freon or other filler gas. If the tube is bent, chafed or punctured, gas will escape and the thermostat will stop responding to temperature changes. Be extremely careful!
Features of tube fastening
In some Atlant models, the capillary tube can be secured with a special bracket or glued to the evaporator. When replacing the thermostat, you must carefully bend the bracket or heat the gluing area with a hairdryer so as not to damage the thin-walled aluminum of the evaporator. The new tube is fixed in the same way, providing maximum thermal contact.
Replacing the sensor in models with the No Frost system
In refrigerators Atlantequipped with the system No Frost, the design of the thermostat and its installation location may differ. Often the thermostat or temperature sensor (if the control is electronic) is hidden behind the back wall of the freezer or in a special technological compartment. This requires deeper disassembly of the unit.
To access the unit, you will have to remove all the shelves and drawers of the freezer, and then dismantle the back panel covering the evaporator and fan. Unlike models with a weeping evaporator, here the thermostat can be attached directly to the air duct or evaporator.
The replacement process includes disconnecting the electrical connectors and carefully removing the sensing element from the socket. In models with electronic control, instead of a mechanical thermostat, a thermistor can be used, which is simply inserted into a plastic pipe.
After installing a new element and assembling all panels, it is necessary to check the operation of the blower fan and defrost heaters, if they were affected during the disassembly process. Incorrect assembly can lead to disruption of air circulation and re-occurrence of temperature problems.
| Refrigerator type | Thermostat location | Difficulty of access | Necessity of defrosting |
|---|---|---|---|
| Single compressor | Inside the refrigerator compartment | Low | Not required |
| No Frost | Behind the back wall of the freezer | Average | Recommended |
| Two-compressor | In each compartment separately | Medium/High | Depends on models |
| Electronic control | In the duct or behind the panel | High | Often required |
Nuances of connecting the electrical part
The electrical circuit for connecting the thermostat in refrigerators Atlant is relatively simple, but requires care. The thermostat usually has two or three terminals. If there are three terminals, then the third is used to connect the compressor operation indicator (light on the front panel), which lights up when the engine is turned off.
When replacing a part, it is extremely important to connect the wires correctly. Mixing up the contacts may result in the refrigerator not turning on or, worse, the indicator lamp burning out and the control circuit not closing. Before disconnecting the wires, be sure to take a photo or draw a diagram.
If the terminal markings on the new thermostat differ from the old one, use a multimeter in dial mode. When the knob is turned to the “maximum” (or “on”) position, the circuit between the main contacts should ring (have zero resistance).
- ⚡ Main contact (L) - connects to the phase wire from the network or relay.
- 🔌 Compressor contact (1 or 2) - goes directly to the start-protection relay motor.
- 💡 Indicator contact (4) - used only in models with light indication of operation.
To connect wires, use reliable methods: soldering followed by insulation or special connecting terminals. Twisting the wires in the refrigerator compartment is unacceptable due to high humidity and the risk of oxidation, which will eventually lead to the appearance of transient resistance and heating.
⚠️ Attention: Before turning on the refrigerator after replacing the thermostat, make sure that no wires touch the metal parts of the case or evaporator. This can cause a short circuit and damage the compressor or wiring.
Setting up and checking operation after replacement
After successfully installing the new thermostat and assembling the refrigerator, the testing phase begins. Do not rush to load products into the chambers - let the unit idle for at least one full cycle of on and off. This will ensure proper operation automation and the absence of cold leaks.
Set the regulator knob to the middle position (usually number 3 or 4). Normally, the compressor should turn on immediately or after a short pause (if there is protection against restarting). After some time, when the temperature in the chamber reaches the set value, a click should be heard and the motor will turn off.
The operating time and idle time of the compressor depend on the ambient temperature and chamber load, but the approximate cycle is 10-15 minutes of operation and 20-30 minutes of rest. If the refrigerator operates in this mode, then the replacement was successful.
If the compressor does not turn off for a long time (more than an hour) or does not turn on at all, it is necessary to re-check the connection diagram and the integrity of the capillary tube. Perhaps the new thermostat is also faulty or does not fit the parameters of your model.
Frequently asked questions (FAQ)
Is it possible to operate the refrigerator without thermostat?
Technically, you can start a compressor without a thermostat by closing the contacts directly, but operating the refrigerator in this mode is strictly prohibited. This will lead to continuous operation of the motor, freezing of food to the point of stone, icing of the evaporator and, ultimately, combustion of the compressor due to overheating.
Why does the new thermostat click, but the refrigerator does not turn on?
If there is a click, it means that the mechanics are working, but the electrical circuit is not closed. Possible reasons: oxidation of new contacts (rare), broken wire in the compressor circuit, malfunction of the start relay or the motor itself. It is necessary to test the circuit with a multimeter.
How to understand that the thermostat does not fit the length of the capillary tube?
If the tube is too long, it can be carefully laid in a ring in the free space without bending. If it’s too short, it’s impossible to reach it. In this case, the thermostat will not read the temperature correctly, and replacing it will not solve the problem. You need to look for an analogue with a suitable length.
Is it necessary to defrost the refrigerator before replacing the thermostat?
For models with a crying evaporator, complete defrosting is not necessary, but is desirable for convenience. For No Frost models, defrosting is often necessary, since access to the sensor may be blocked by ice or require the removal of panels, which become fragile at low temperatures.