When the refrigerator Ariston no longer maintains the set temperature, food begins to deteriorate, and ice appears on the walls or, conversely, the ice completely disappears. Often the cause of such malfunctions is the failure of thermostat the device that controls the temperature inside the chamber. Owners of household appliances often encounter difficulties when trying to find this unit, since its location depends on the specific model and design of the unit.
In this article we will analyze in detail where the thermostat is located in the Ariston refrigerator, how to get to it and what to look for when diagnosing. Thermoregulator may be hidden under decorative panels or built into the control system, so understanding your model is critical before starting any work. Improper handling of electrical components can lead to worsening damage.
Before proceeding with disassembly, it is necessary to de-energize the equipment. Ariston refrigerator is a complex mechanism where each element plays its role. We will look at the main signs of a malfunction, the algorithm for searching for a part, and nuances that will help you save time and money on calling a technician. Remember that accurate knowledge of the location of the unit is half the success of the repair.
Principle of operation and signs of malfunction of the thermostat
The thermostat, or thermostat, is the “brain center” of the cooling system, responsible for turning the compressor on and off. When the temperature inside the chamber reaches the set value, the contacts open and the motor-compressor stops. If temperature sensor fails, the refrigerator may work non-stop, causing freezing, or not turn on at all, leading to defrosting of food.
The breakdown can be determined by a number of characteristic symptoms that appear in the operation of the equipment. Pay attention to the following signs:
- 🔊 The compressor hums continuously, without turning off even when the temperature reaches a low temperature.
- 🧊 A “coat” of ice forms in the refrigerator compartment or, conversely, the food begins to thaw.
- 💡 The light inside the chamber is constantly on, even when the door is closed (an indirect sign of sticking contacts).
- ❄️ Large ice deposits appear on the back wall, and the refrigerator body itself becomes very hot.
It is important to understand that similar symptoms can be observed when there is a freon leak or a compressor malfunction. However, if you hear a characteristic click when you turn the control knob (in mechanical models), but the compressor does not start, the problem most likely lies in thermostat. In electronic models Ariston the role of a thermostat is performed by a sensor, the readings of which are processed by an electronic module.
⚠️ Attention: If the refrigerator makes strange sounds or you smell a burning smell, immediately unplug it. Attempts to diagnose live electrical circuits are deadly.
Diagnostics should begin with a visual inspection and listening to the operation of the unit. Often the problem lies in oxidation of the contacts or mechanical damage to the capillary tube. In models with electronic control, failures can be caused by power surges in the network, which disables sensitive electronics.
Design features of Ariston refrigerators
Refrigerators Ariston, like equipment from many other brands, are divided into two main types according to the temperature control system: mechanical and electronic. This directly determines where exactly the desired element will be located. In older and budget models, it is most often used a mechanical thermostat, which is a device with a rotary handle and a long sensitive tube.
In more modern models equipped with a system No Frost or an electronic display, the adjustment knob on the body can be absent. In such cases, control is carried out through a panel on the door, and the sensor (thermistor) itself is located directly inside the chamber or in the air circulation system. Replacing it requires deeper disassembly and the use of a multimeter to check the resistance.
Particular attention should be paid to two-chamber models. They can have two independent control circuits installed, but most often the thermostat controls only the refrigerator compartment, while the freezer operates on the residual principle or has its own separate sensor in the systems No Frost. Understanding this difference will help you not to look for extra parts where they physically cannot be.
Refrigerator cases may also differ in the way the internal panels are attached. In some models, to access the components, it is enough to remove the lampshade; in others, you will need to dismantle the entire back wall of the camera. Prepare in advance a set of screwdrivers with different tips, including Phillips and flathead, as well as a spatula for carefully removing the plastic latches.
Looking for a thermostat in models with mechanical controls
If yours Ariston refrigerator is equipped with a rotary knob for adjusting the temperature located inside the chamber or on front panel, then you are dealing with a mechanical thermostat. In the classic version, this unit is located directly under the adjustment knob. To get to it, you need to carefully remove the plastic regulator and decorative trim.
The dismantling process usually looks like this: the handle is simply removed by hand (sometimes it is held on a slot), after which the screws holding the thermostat housing are unscrewed. Under the body you will see the block itself with contacts and the one coming out of it capillary tube. This tube goes deep into the refrigerator body and ends with a sensitive element, which is attached to the evaporator or chamber wall.
It is important not to damage the capillary tube when removing the thermostat. It is filled with gas or liquid, and any depressurization will cause the new or old device to stop working. The length of the tube may vary, and it must be carefully pulled out of the technological channel without using excessive force.
☑️ Preparing to replace the thermostat
In some modifications, the thermostat may be shifted to the side and hidden behind the lampshade. If there is nothing under the control knob, try removing the plastic lamp cover. Manufacturers often hide electrical components in a niche above the user's head in order to save space inside the useful volume of the chamber.
Location of the sensor in electronically controlled refrigerators
In models with electronic control (Electro Control) the situation is different. There is no usual “twist” with a long tube. The thermostat function is performed by a small electronic sensor - a thermistor, which changes its resistance depending on the ambient temperature. Finding it visually is more difficult, since it is often disguised as elements of the interior of the chamber.
Most often, the temperature sensor in the fridge compartment Ariston with electronics is located in one of the following places:
- 📍 Behind the rear wall of the fridge compartment (removal of the plastic panel is required).
- 📍 In the evaporator area, hidden behind the decorative box.
- 📍 In the cold air supply channel (for systems No Frost).
- 📍 Next to the lighting lamp or in the upper part of the chamber.
To access the sensor in most cases it is required partially defrosting the refrigerator and removing the back wall of the chamber. This is a labor-intensive process that requires care not to break the plastic latches, which become fragile in the cold. The sensor is usually fixed in a special socket and connected to the control board via a connector.
⚠️ Attention: The plastic of the internal panels of the refrigerator becomes very brittle at low temperatures. Before removing the walls, let the refrigerator stand unplugged for at least 2-3 hours at room temperature.
Checking such a sensor is only possible using a multimeter in resistance measurement mode. Normal readings vary depending on the specific model and temperature, but they are typically a few kiloohms at room temperature and change dramatically when cooled. If the resistance is infinite or equal to zero, the sensor is faulty and requires replacement.
Replacement algorithm and important nuances
Replacing thermostat or a sensor is a procedure that requires care. After you have found the faulty element and purchased a new one (be sure to check the markings!), you can begin installation. In mechanical models, the main thing is to correctly install and fix the capillary tube in the same position in which it was originally. The bends of the tube should follow the original trajectory.
When installing an electronic sensor, it is important to ensure tight contact with the surface that it must control. Often the sensor is inserted into a special hole in the evaporator and secured with sealant or a clamp. Poor contact will lead to incorrect temperature readings and malfunctions of the compressor.
What happens if the wires are mixed up?
When connecting the wires to a new thermostat, it is important to remember or photograph their original position. Mixing up the wires can lead to a short circuit or failure of the control board. If you are not confident in your abilities, it is better to contact a professional.
After assembling all the components and connecting the refrigerator to the network, do not rush to load the products. Let the unit run idle for 4-6 hours. This will allow the system to enter operating mode and make sure that the thermostat correctly turns off the compressor when the specified parameters are reached.
The table below shows approximate codes and types of thermostats that can be found in various equipment, however for Ariston it is important to select an analogue for compatibility:
| Device type | Approximate marking | Where used | Installation features |
|---|---|---|---|
| Mechanical | TAM-133, K-59 | Old models, single-chamber | Requires precise installation of the tube |
| Electronic sensor | Models with display, No Frost | Requires disassembly of the evaporator | |
| Defrost thermostat | Defrost thermostat | No Frost systems | Controls defrosting, not cooling |
Do not forget that the marking NTC means negative temperature coefficient of resistance. This is standard for most modern refrigerators. Using a sensor with other characteristics will lead to incorrect operation of the entire cooling system.
Common mistakes during self-repair
Do-it-yourself refrigerator repair Ariston often involves the risk of making a mistake, which can cost more than the services of a specialist. One of the most common mistakes is an attempt to replace a mechanical thermostat with a universal one without taking into account the length of the capillary tube. If the tube is too long, it will have to be folded, which may disrupt the circulation of the refrigerant inside it, and if it is short, it simply will not reach the mounting point.
Another common problem is ignoring the tightness. When removing sensors in systems No Frost the channel insulation is often broken. Moisture from the chamber air can penetrate to the evaporator, causing rapid ice formation and clogging of the condensate drainage channels. Always check the condition of the seals after disassembly.
Also, users often forget to check the condition of the contacts in the circuit. Oxidized or burnt contacts may be the cause of the malfunction, not the thermostat itself. In such cases, replacing an expensive unit will be a waste of money. Stripping the contacts or replacing the terminal block may solve the problem.
⚠️ Attention: Technical characteristics and location of components may vary slightly depending on the year of manufacture and the specific modification of the refrigerator. Always check the technical documentation of your model before starting work.
Questions and answers
Is it possible to temporarily bypass the thermostat to make the refrigerator work?
Theoretically, if you close the wires going to thermostat, the compressor will start working. However, this is strictly not recommended for continuous use. The refrigerator will work non-stop, which will lead to freezing of food, breakdown of the compressor due to overload and high energy consumption. This is only permissible as a short-term measure to check the compressor.
Why does the refrigerator not turn off after replacing the thermostat?
There may be several reasons: the adjustment screw is incorrectly adjusted (if there is one), the capillary tube is installed incorrectly (not deep enough or does not make good contact), or a thermostat with an inappropriate temperature range is selected. It is also worth checking the system for freon leakage.
Where can you find the thermostat markings in an Ariston refrigerator?
The markings are usually applied to the metal or plastic body of the thermostat itself. To see it, you need to remove the regulator handle and the protective cover. In electronic models, the marking is located on the sensor itself, access to which is often blocked by the back wall of the chamber.
How much does it cost to replace a thermostat in a service center?
The cost consists of the price of the spare part and the work of the technician. On average, replacing a mechanical thermostat is cheaper than diagnosing and replacing an electronic sensor, as it requires more disassembly time. The exact price can only be found out after diagnosing a specific model.