Search thermostat in refrigeration equipment Hotpoint Ariston often becomes the first step when trying to repair it yourself. If yours stops turning on or, conversely, works nonstop, the problem most likely lies in the temperature control system. Understanding the design of the unit will allow you to save time and avoid calling a technician for simple diagnostics.
In most models of this brand, the temperature sensor is hidden from the user’s eyes, which requires partial disassembly of the interior of the chamber. It is important to immediately note that in modern electronically controlled refrigerators, instead of a mechanical thermostat, thermal sensoris used, which is a small resistor. The location of these elements varies depending on the type of control and the year of manufacture of the device.
Before proceeding with dismantling the panels, you must disconnect the device from the power supply. Safety is the number one priority when working with home appliances. Further actions will depend on what kind of modification Ariston is installed in your kitchen: with a mechanical handle or with a digital display.
⚠️ Attention: Any work on disassembling the refrigerator should be carried out only after completely disconnecting the device from the electrical network to avoid electric shock.
Differences between mechanical and electronic control
The first thing the owner needs to determine is the type of temperature control system. Older and budget models Hotpoint Ariston use classic mechanical thermostat. This device is a box with a capillary tube that responds to the expansion of gas or liquid inside the tube. Typically, such models have a rotary knob inside the chamber with numbers from 1 to 7.
In more modern units, especially with the system No Frost, mechanics are replaced with electronic sensors. There is no long curved tube here, but a compact one, enclosed in a plastic case. It transmits an electrical signal to the control module, which already makes the decision to start the compressor. An error in determining the type of device will lead to the purchase of the wrong spare part. thermal sensor, enclosed in a plastic case. It transmits an electrical signal to the control module, which already makes the decision to start the compressor. An error in determining the type of device will lead to the purchase of the wrong spare part.
If you see a control knob inside the refrigerator compartment, it means you have a mechanical system. If the adjustment is made using buttons on the outer door, but the inside is clean and smooth, then you need to look for an electronic sensor. In some hybrid models, the mechanical regulator may be located on the external panel, but the operating principle remains similar to the classic one.
- 🔧 A mechanical thermostat more often fails due to loss of tightness of the capillary tube.
- ⚡ Electronic sensors are less likely to break, but are sensitive to power surges in the network.
- 📏 The capillary tube of a mechanical device can reach a length of up to 2.5 meters.
Localization of the thermostat in refrigerators with a drip system
In classic two-chamber refrigerators Hotpoint Ariston with a drip defrosting system thermostat almost always located inside the refrigeration chamber. The standard installation location is the upper right corner, under the plastic cover. Exactly where the light bulb or ventilation hole is usually located.
To access the assembly, you must carefully remove the plastic cover. It can be secured with latches or screws. Under the cover you will see a rectangular or square block with wires going into it and also a long corrugated tube going out. This is the required one capillary, the end of which is fixed to the evaporator behind the rear wall.
It is important not to damage the fragile capillary tube during dismantling. If it breaks or a crack appears in it, the refrigerant will evaporate and the refrigerator will stop freezing. In such cases, it is not just a replacement of the thermostat that is required, but a complex charging of the system, which cannot be done without special equipment.
Sometimes manufacturers hide the thermostat housing deeper, behind the decorative ceiling panel of the chamber. In this case, you may need to unscrew several screws. Be careful: the fasteners may be hidden under plastic plugs or stickers.
The location of the sensors in the No Frost system
Refrigerators Hotpoint Ariston with the system No Frost are more complex. Here, the thermostat (more precisely, the temperature sensor) is often located not in the main chamber, but in the evaporator area, which is hidden behind the rear panel. However, for initial diagnostics it is often enough to check the accessible elements without disassembling the entire unit.
In models with electronic control, the main air temperature sensor may be located in a special duct on the ceiling of the refrigeration chamber or in the air duct between the chambers. It is a small plastic cylinder with two wires. You can get to it by removing the top plastic shelf or decorative cover.
If we are talking about the defrost sensor, which is also often confused with a thermostat, then it is located directly on the evaporator in the freezer. To replace it in models No Frost often requires complete dismantling of the rear wall of the freezer, which is a labor-intensive procedure.
| Sensor type | Location | Appearance | Function |
|---|---|---|---|
| Thermostat (mech) | Upper right corner of HK | Box with tube | Compressor on/off |
| Sensor air | Ceiling HC / Air duct | Plastic cylinder | T° control in the chamber |
| Defrost sensor | Evaporator (Freezer) | Metal probe | Defrost control |
| Condenser sensor | Rear of the unit | On the condenser tube | Overheat protection |
Why are No Frost sensors more difficult to replace?
In the No Frost system, access to the sensors is often blocked by a massive evaporator and fan. Replacement may require defrosting the unit for 24 hours to safely remove ice and avoid damaging the aluminum heat exchanger tubes. In addition, it is often necessary to dismantle the entire back panel of the freezer, which requires care with fragile plastic.
Instructions for dismantling and accessing the unit
The process of gaining access to thermostat requires a minimal set of tools: a Phillips screwdriver, a flat-head screwdriver for unsnapping latches and possibly pliers. Start by emptying the refrigerator compartment of food and removable shelves so that nothing interferes with the view.
Locate the plastic cover in the upper right corner. Gently pry it off with a flathead screwdriver. If the cover is attached with screws, remove them. Proceed without excessive force, as the plastic in old refrigerators Ariston becomes brittle and can crack.
After removing the cover, you will see the thermostat housing. It can be mounted on a bracket or simply inserted into a groove. Disconnect the connector with the wires: the wires may be tightly fixed, use side cutters only as a last resort, it is better to release the terminals carefully.
☑️ Procedure for dismantling
The most difficult part is removing the capillary tube from the channel. It can be glued or simply inserted tightly. Pull it slowly, without jerking, being careful not to bend or break it. If the tube goes inside the canal, it will be extremely difficult to pull it back out.
Diagnostics and signs of malfunction
How to understand what thermostat really faulty? The most obvious sign is that the refrigerator does not turn on at all, although the light inside is on and there is voltage in the socket. The compressor is silent, although it should start according to a timer or when the temperature rises.
The second option is that the unit operates continuously without turning off. In this case, the food freezes in the refrigerator compartment, a thick crust of ice forms on the walls, and the compressor gets very hot. This indicates that the contacts inside the thermostat are “stuck” in the closed state.
For an accurate check, you can use a multimeter in dial mode. At room temperature, the mechanical thermostat contacts should ring (show zero). If you remove the thermostat sensing tube into a container with ice and water, the contacts should open after a while (depending on the setting), and the device will indicate an open circuit.
⚠️ Attention: If, after replacing the thermostat, the refrigerator began to freeze less or more than usual, the new regulator may have a different temperature characteristic. Make sure the markings on the new part match the original.
Frequent replacement errors and expert advice
One of the most common mistakes is incorrect installation of the capillary tube. Its sensitive end should fit tightly to the surface of the evaporator in a specially designated place. If the tube hangs in the air or touches the chamber wall, thermostat it will read the wrong temperature.
Another mistake is using the wrong analogue. Thermostats Hotpoint Ariston can have different capillary lengths (for example, 60 cm, 120 cm, 200 cm) and different temperature response ranges. Installing a tube that is too long will result in it breaking, and a tube that is too short will result in the inability to reach the sensor to the control zone.
Also, users often forget to check the condition of the door seal after repair. If the door does not close tightly, warm air enters the chamber, and even a working thermostat will force the compressor to work in increased mode, trying to compensate for heat loss.
- ❄️ Always check the tightness of the connection between the capillary tube and the evaporator.
- 🔌 Make sure that the terminal block is dry and not oxidized before connecting.
- 🧊 After replacing, let the refrigerator operate for 2-3 hours without loading food to stabilize the mode.
Remember that modern refrigerators are complex devices. If you are not confident in your abilities or are afraid of damaging the cooling system, it is better to contact an authorized service center. However, for many enthusiasts, self-repair becomes a way to extend the life of their favorite equipment.
Is it possible to install a thermostat from another brand, for example, from Indesit?
Often refrigerators Hotpoint Ariston i Indesit have a similar design, since they are manufactured in some factories. Mechanical thermostats can be interchangeable if the mounting dimensions, capillary tube length and temperature response parameters are the same. However, it is better to look for original spare parts or proven analogues with markings corresponding to your model.
Why does the refrigerator make strange sounds after replacing the thermostat?
The new thermostat may have slightly different characteristics, due to which the compressor will turn on more often or less frequently, which may change the acoustic background. The capillary tube itself can also produce sound if it is not secured tightly and vibrates when the compressor is operating. Check the reliability of all elements.
How often should you change the thermostat in the refrigerator?
The service life of a mechanical thermostat is on average 5-7 years, but it can last 10-15 years in gentle conditions. Electronic sensors are usually more durable and fail less often, usually due to power surges or manufacturing defects. Scheduled replacement is not required, they are replaced only if there is a malfunction.