Where is the temperature sensor in the Ariston refrigerator: search and replacement

Modern refrigerators Ariston are complex climate systems, where each element plays a critical role in maintaining food freshness. Thermal sensor (thermostat) acts as the “eye” of the unit, continuously monitoring the temperature inside the chambers and sending signals to the compressor about the need to turn on or off. If you notice that the refrigerator has stopped freezing or, on the contrary, has begun to freeze food to the point of stone, the first thing you should suspect is this particular component.

Understanding where the sensor is located is necessary not only for replacing it, but also for correct diagnosis. In different models of refrigerators Ariston —whether they are classic two-chamber models or modern ones No Frost —the location of the sensors can be radically different. In some cases they are hidden behind plastic panels, in others they are built into the evaporator or are located in close proximity to the lighting lamps. An error in the search can lead to damage to the fragile evaporator tubes or a violation of the tightness of the system.

In this article we will analyze in detail the architecture of refrigeration chambers Ariston, consider the main signs of thermostat failure and provide a step-by-step algorithm of actions. You will learn to distinguish problems with the sensor from compressor malfunctions or freon leaks.

The principle of operation and types of sensors in Ariston refrigerators

Before looking for the physical location of the element, you need to understand what exactly we are dealing with. Refrigerators Ariston use several types of sensors, each of which is responsible for its own area of ​​operation. The main one is thermostatwhich mechanically or electronically opens the compressor power circuit when the specified parameters are reached.

In more modern models with a system No Frost and electronic control, digital thermistors are used. They are highly accurate and transmit data to the main control module. Capillary thermostat, characteristic of older models, is a long tube sealed at the end, which expands or contracts depending on the air temperature.

• 🌡️ Mechanical thermostats: They work based on the physics of gases, often have an adjustment screw and are located in the user's access area or behind the decorative panel.
• 💻 Electronic thermistors: Miniature elements that transmit resistance that changes with temperature require a multimeter to check.
• ❄️ Defrost sensors: Responsible for controlling the defrost of the evaporator in No Frost system, preventing overheating of the heating element.

Incorrect interpretation of the sensor type may lead to the purchase of the wrong spare part. For example, installing an electronic resistor instead of a mechanical relay is impossible without re-soldering the control circuit. Therefore, before starting work check the technical documentation or markings on the product itself.

⚠️ Attention: Electronic sensors are extremely sensitive to static electricity. If you touch the contacts with your fingers or metal tools without grounding, you can irreversibly damage the sensing element, even if it is visually intact.

It is also worth noting that in two-compressor models Ariston sensors can be installed independently in the freezer and refrigerator compartments. This allows you to maintain different temperature conditions, but complicates diagnostics, since a malfunction of one sensor does not always block the operation of the entire unit.

Where to look for the sensor in models with mechanical control

In classic refrigerators Ariston with a mechanical temperature control knob inside the chamber, the sensor is most often integrated directly into the regulator body or displayed in the form capillary tube. If you open the door and see a rotary knob with numbers from 1 to 7, then the thermostat is located immediately behind it.

To access it, you must carefully remove the plastic handle. Usually it is simply pulled together by hand or pryed with a flat screwdriver through a special hole. Under the handle you will see a rod going deep into the panel and a fastening nut. This is where the the actuatoropening contacts are located.

The capillary tube coming from this unit can be fixed to the rear wall of the refrigerator compartment or mounted in a special channel inside the wall. In older models, the end of the tube often hung freely inside the chamber, but in modern ones Ariston it is securely fixed with clips. The length of the tube varies, and it is this that transmits the thermal expansion of the gas to the contact group.

If the refrigerator does not turn on, but the light is on, the problem often lies in sticking contacts inside this mechanical unit. Tapping the thermostat housing sometimes helps to temporarily start the compressor, which confirms the diagnosis. However, this is only a temporary measure, and replacement of the unit is inevitable.

In some modifications, the thermostat can be hidden behind the decorative cover of the lighting lamp. The light bulb and thermostat are often grouped into a single unit for ease of installation. Removing the lampshade provides access to the electrical contacts and the body of the sensor.

The location of temperature sensors in the No Frost system

Refrigerators Ariston with the system No Frost are more complex. There is no frost on the walls, since the air circulates forcibly, and the evaporator is hidden behind the rear panel. Temperature sensors in such models are often located in the air circulation area or directly on the evaporator.

The main sensor that controls the temperature in the refrigerator compartment may be located in the air duct through which cold air comes from the freezer. To get to it, you will need to remove the back wall of the refrigerator compartment. This requires dismantling the shelves, side rails and possibly the air supply system.

• 🔍 Evaporator area: The defrost sensor is attached to the evaporator tubes (often in the lower or middle part) and monitors the defrosting process.
• 💨 Air ducts: Sensors can be built into the plastic boxes along which it moves air to read the temperature of the flow, and not of static air.
• 🧊 Freezer compartment: In two-chamber No Frost, a separate sensor monitors the temperature in the freezer, often located closer to the exit from the evaporator.

It is important not to confuse the temperature sensor with Defrost heating element or a timer. The heating element looks like a curved metal tube, often with fins, and the sensor is a small plastic cylinder or capsule with two wires. An error during replacement can lead to a short circuit.

⚠️ Attention: When removing the back panel in the No Frost system, be extremely careful. Plastic becomes brittle in the cold, and behind the panel there are aluminum evaporator tubes that can be easily damaged by tools. A breakdown of the tube will lead to a freon leak and expensive repairs.

Often in models Ariston with electronics, sensors have specific connectors. When dismantling, do not pull the wires - disconnect the chips by pressing the latches. A wire break at the very base of the sensor is a common problem with careless maintenance.

Diagnostics: how to check the serviceability of the sensor

Before ordering a new part, you need to make sure that the problem is in the sensor, and not in the compressor or start relay. The most reliable diagnostic method is testing with a multimeter. For mechanical thermostats, the test is carried out for the presence of contact closure at a certain temperature.

To check, remove the sensor and cool it (you can put it in the freezer for 15-20 minutes, if the design allows it, or use a freezing spray). Then connect the multimeter probes in dial mode to the contacts. If the sensor is working properly, when it heats up in your hand, it should “click” and change the resistance (or close/open the circuit).

Electronic thermistors are checked by measuring resistance. The values ​​depend on the specific model Ariston, but usually at room temperature (+25°C) the resistance is about 5-10 kOhm, and when freezing (-18°C) it increases sharply. Resistance tables (R-T characteristics) can be found in service manuals.

If the multimeter shows infinity (open) or zero (short circuit) in any temperature mode, the sensor is faulty. Also, a sign of a breakdown is a situation when the refrigerator “threats” without stopping or does not turn on at all, while other components are working properly.

In models with electronic control, a faulty sensor often causes temperature indicators to appear on the display or blink. For example, a flashing alarm light may indicate a loss of signal from the temperature sensor. error code on the display or flashing temperature indicators. For example, a flashing alarm light may indicate a loss of signal from a temperature sensor.

Table of common faults and symptoms

To simplify diagnostics, we provide a summary table that will help compare the symptoms of your refrigerator Ariston with a possible cause associated with sensor.

This table covers the most common scenarios. However, it is worth considering that similar symptoms can be caused by other problems, for example, a freon leak or a faulty start relay. An integrated approach to diagnostics always gives the best result.

If you have replaced the sensor, but the problem persists, the problem may be in the control module, which does not process signals correctly. In such cases, professional flashing or replacement of the board is required.

Step-by-step instructions for replacing the sensor

Replacing the sensor in the refrigerator Ariston is a procedure accessible to a home craftsman, but requiring care. The main rule is to completely disconnect from the power supply before starting work. Find an outlet or unplug it from the network.

First, remove all interfering elements: shelves, drawers, lighting lamp. Remove the decorative panels blocking access to the assembly. If the sensor is mechanical, unscrew the mounting nut and pull out the old thermostat along with the capillary tube. Pay attention to how the tube was laid - it must not be bent or twisted.

For electronic sensors, the process is simpler in terms of physical access, but requires care with the wires. Disconnect the chip of the old sensor, remove it from its seat (often it is simply inserted into a hole in the plastic or glued with thermal paste). Install a new sensor, connect the connector.

After assembly, turn on the refrigerator and let it work for 2-3 hours without loading food. This is necessary to stabilize the temperature and check the cyclic operation of the compressor. If the refrigerator got cold and turned off, the replacement was successful.

⚠️ Attention: Never use glue not intended for low temperatures or regular tape to attach the sensors. In cold weather, they lose their properties, and the sensor may fall off, which will lead to incorrect temperature readings.

In some cases, it may be necessary to set up a new thermostat. On mechanical models there is an adjusting screw, but you should only turn it if you have pressure gauge equipment. It is better to leave the factory settings.

Frequently asked questions (FAQ)