Sudden defrosting of food or, conversely, the transformation of fresh vegetables into ice blocks often signals a malfunction of the temperature control system. In refrigerators Ariston the thermostat is responsible for maintaining the set mode, which can fail for various reasons. Understanding the principle of its operation and the ability to carry out initial diagnostics will allow you to save significant money on calling a technician or avoid damage to a large supply of food.
Before you begin disassembling the unit, you must clearly understand what exactly you are looking for. Thermostat is an electromechanical device that opens or closes the electrical circuit of the compressor depending on the temperature in camera. If this element “sticks” in one position, the refrigerator either stops turning on or works non-stop, ignoring the set settings.
Self-check requires a minimum set of tools and compliance with safety precautions. It is important to understand that not all symptoms point specifically to the temperature regulator; sometimes the problem lies in a freon leak or a malfunction of the start relay. However, statistics show that thermostat is one of the most common causes of temperature violations in household refrigerators.
Main signs of thermostat malfunction
The first step in diagnosis is careful monitoring of the operation refrigeration equipment. If you notice that the compressor is humming almost without interruption, and a “coat” of ice has formed inside the chamber, this is a sure sign that the circuit is not opening. In such a situation, thermostat “thinks” that the temperature is not low enough, and continues to keep the contacts closed, causing the motor to wear out.
The opposite situation, when the refrigerator is silent and warm inside, may also indicate a sensor failure. In this case, the contacts could oxidize or burn out, and the signal to start the engine simply does not arrive. Sometimes users confuse these symptoms with a burnout of the compressor itself, but checking thermostat allows you to exclude this expensive part from the list of suspects.
- 🧊 The compressor works continuously, not turning off even at night, while the chamber is too cold.
- 🌡️ The refrigerator has completely stopped cooling, although the light inside is on and the network is working properly.
- 💧 The appearance of large puddles of water under the unit or on the kitchen floor due to frequent thawing.
- 🔌 Spontaneous switching on and off at very short intervals (less than 2-3 minutes).
⚠️ Attention: If the compressor housing is hot and the refrigerator compartment is warm, the problem may not be in the thermostat, but in a refrigerant leak or a clogged capillary tube. Do not rush to change parts without checking the pressure in the system.
Particular attention should be paid to models with mechanical control, where the regulator handle is located inside the chamber or on the front panel. If you do not hear a characteristic click when you turn the handle, this may indicate a mechanical jamming of the internal mechanisms. In electronic models Ariston with a display, a malfunction is often accompanied by an error code, which can be deciphered in the instructions.
Preparation for diagnostics: tools and safety
For a quality check thermostat you will need a basic home repair kit. The main tool will be a multimeter (tester), which allows you to measure the resistance of the circuit. Without this device, diagnostics will be of an exceptional nature, since it is impossible to visually determine the integrity of the internal contacts.
Before starting any work, it is absolutely necessary to turn off the power to the refrigerator. Unplug the power cord from the outlet and make sure there is no voltage at the plug. Even briefly touching live parts under load can lead to serious injury or electric shock, so ignoring this rule is unacceptable.
☑️ Preparing to check the thermostat
In addition to the multimeter, prepare a flathead and Phillips screwdriver for removing the panels, as well as pliers in case you need to carefully bend the fasteners. If you have access to industrial alcohol or contact spray, they may be useful for cleaning the contacts before reassembling, although this will not help if there is an obvious breakdown.
| Tool | Purpose | Importance |
|---|---|---|
| Multimeter | Measuring resistance (continuity) | Critically important |
| Screwdrivers | Removing panels and covers | Necessary |
| Pliers | Working with terminals and clamps | Advisable |
| Flashlight | Lighting hard-to-reach places | Recommended |
It is also recommended to prepare a container in advance for food that may defrost during a long period of inactivity of the refrigerator during diagnostics and repairs. The longer the check lasts, the higher the risk of increasing the temperature inside the chambers, so act quickly, but without unnecessary haste.
Where is the thermostat in Ariston refrigerators
The location thermostat directly depends on your model Ariston and the year of its manufacture. In classic two-chamber refrigerators with one compressor, the sensor is most often hidden under a plastic cover inside the refrigerator compartment, next to the light bulb or temperature control knob.
In more modern models with the system No Frost access to the thermostat may be complicated by the presence of additional thermal insulation or decorative panels. Sometimes, to gain access, it is necessary to remove the top cover of the case or dismantle the lamp shade, which is often secured with latches.
Hidden installation locations
In some Ariston models, the thermostat can be hidden behind the back wall of the refrigerator compartment or integrated into the control unit, which requires partial disassembly of the case. Carefully inspect all accessible hatches before removing the main panels.
The capillary tube, which is the sensitive element of the thermostat, is usually attached to the evaporator or inserted into a special sleeve. When removing the old sensor, it is important not to damage this thin tube, since its deformation will lead to incorrect operation of even a new device. Carefully inspect the mounting location and remember exactly how the tube was fixed.
⚠️ Attention: When dismantling the plastic panels inside the chamber, proceed carefully, especially if the refrigerator is old. Plastic becomes brittle in the cold and can easily crack from careless movement.
Step-by-step instructions: how to check a thermostat with a multimeter
After you have reached the thermostat, you need to remove the wire terminals from it. Before doing this, be sure to photograph or sketch the connection diagram so that you do not mix up the contacts during assembly. An error in the connection can lead to a short circuit or improper operation of the compressor.
Set the multimeter to resistance measurement mode (usually indicated as 200 Ohms or the beep icon). Touch the tester probes to the thermostat contacts. If the device shows “infinity” or one in the most significant digit, it means that the circuit is open, which at room temperature may be the norm for some types of relays, but requires checking in the cold.
- 🔧 Remove the thermostat and place its sensitive part (capillary) in a container with cold water (about +3...+5°C).
- ❄️ Wait 10-15 minutes, simulating the operating temperature inside the refrigerator.
- 📉 Repeat the measurements with a multimeter: the resistance should drop to zero and the device should emit a beep.
- 🔥 When the sensor heats up in your hands or warm water, the circuit should break again (resistance is infinity).
If the circuit does not close when cooling, and does not open when heating, thermostat is considered faulty and requires replacement. It is important to note that checking “by ear” (clicks) is not always informative, since the contacts inside may burn out and not conduct current, even if the mechanism clicks.
In some cases, the problem may lie not in the sensor itself, but in oxidized connector contacts. Cleaning the contacts with alcohol and tightening them sometimes returns the device to functionality, but this is only a temporary measure. It is safer to install a new original component.
Replacing the thermostat: important nuances
If diagnostics have confirmed a malfunction, the only correct solution is to replace the element. When purchasing a new one, pay attention not only to compatibility with the brand, but also to the length of the capillary tube and temperature range. Universal models may not work correctly if their parameters do not match the original. thermostat pay attention not only to brand compatibility Ariston, but also on the length of the capillary tube and the temperature range. Universal models may not work correctly if their parameters do not match the original.
The process of installing a new sensor is performed in reverse order. Carefully insert the capillary tube into the seat, being careful not to bend it at an acute angle. Secure the thermostat body and connect the wires according to the diagram or photograph made earlier.
After assembling and connecting the refrigerator to the network, let it work for several hours without loading food. This will allow the system to enter mode and make sure that the new thermostat correctly controls the cycles of turning the compressor on and off.
Common mistakes during self-repair
One of the most common mistakes is an attempt to “reanimate” an old thermostat by tapping or heating. Such actions may give a short-term effect, but soon the problem will return, perhaps at the most inopportune moment, when the refrigerator has a full supply of food.
Another mistake is ignoring the condition of the door seals during diagnosis. If the door does not close tightly, warm air enters the chamber, and a working thermostat will constantly keep the compressor on, trying to compensate for heat loss. In this case, replacing the sensor will not solve the problem.
Some amateur craftsmen try to short-circuit the thermostat contacts so that the refrigerator works constantly. This is a serious mistake that leads to freezing of the evaporator, breakdown of the compressor and a significant increase in electricity consumption. Thermoregulator - a vital element, without which normal operation is impossible.
⚠️ Attention: Technical characteristics of refrigerators may vary depending on the specific modification. Before ordering spare parts, check the part numbers with the data in the device passport or on the manufacturer's official website.
FAQ: Frequently asked questions
Is it possible to temporarily operate a refrigerator with a jumper instead of a thermostat?
Technically, you can start the compressor by short-circuiting the wires, but doing this is strictly not recommended, even as a temporary measure. Without temperature control, the food in the chamber will freeze, and the compressor may burn out from overheating or water hammer with liquid freon.
Why does the new thermostat click, but the refrigerator does not turn on?
Probably, the problem is not in the thermostat, but in the compressor start relay or the engine itself. It is also worth checking the integrity of the wires going from the thermostat to the motor and the presence of voltage in the socket.
How often do you need to change the thermostat in an Ariston refrigerator?
The service life of the thermostat is not strictly limited in time and depends on the intensity of use. On average, they last 5-7 years, but they can fail even earlier due to power surges or mechanical damage.
Does defrosting affect the operation of the thermostat?
Regular defrosting prolongs the life of all components of the refrigerator, including the thermostat. The accumulation of ice on the evaporator distorts the temperature sensor readings, causing it to operate in an incorrect mode.