Faced with the fact that your Biryusa refrigerator stopped turns off or, conversely, does not freeze enough, the first thing that comes to the mind of an experienced technician is checking the thermostat. It is this small device that is responsible for maintaining the set temperature inside the chambers by opening and closing the electrical circuit of the compressor. Understanding where the thermostat is locatedis a key step for self-diagnosis of the malfunction.
In most cases, to access this unit, you do not need to completely disassemble the unit or call a service center team. The design of refrigerators Biryusa, especially popular models with a bottom freezer, allows you to reach the sensor through the inside of the refrigerator compartment. However, it is important to act carefully so as not to damage fragile plastic or insulation.
In this article we will analyze in detail the search algorithm, methods for checking the functionality of the regulator and the nuances of replacing it. You'll learn how to distinguish a broken thermostat from other problems, such as a freon leak or problems with the start relay. Correct diagnostics will save you time and money, allowing you to avoid purchasing unnecessary spare parts.
The principle of operation and signs of malfunction of the thermostat
The thermostat, or thermostat, is an electromechanical device that responds to changes in temperature in the evaporator or directly in the air environment of the chamber. Inside the case there is a bellows tube filled with freon gas, which, when cooled, contracts, opening the contacts, and when heated, expands, closing the circuit. Models Biryusa refrigerators most often use mechanical regulators of the TAM or K-59 series, which have proven themselves to be reliable, but wear out over time.
You can determine that the problem lies in the regulator by a number of characteristic symptoms. If the compressor runs continuously without turning off for hours, and ice forms in the chamber or the food freezes, this is a sure sign of contacts sticking in the closed position. The opposite situation, when the unit does not turn on at all or operates in very short cycles, also indicates a loss of bellows tightness or oxidation of the contacts.
⚠️ Attention: If your refrigerator makes a loud click when you try to turn on, but the compressor does not start, the problem may not be in the thermostat, but in the start relay or the motor itself. Do not rush to change the regulator without first checking the voltage at the terminals.
Sometimes a malfunction manifests itself in the form of incorrect operation of the indicators or the adjustment knob. You can turn the knob from minimum to maximum, but the temperature in the chamber will not change. In such cases mechanical wear the internal parts make the device insensitive to rotation. It is also worth paying attention to the condition of the bellows tube: if it is damaged or deformed, the gas evaporates and the thermostat stops responding to heat.
A multimeter is often required for an accurate diagnosis, but the initial assessment can be done visually and by ear. If, when you turn the knob, you do not hear the characteristic click of the contacts opening, this is an alarming signal. In modern electronically controlled models, the role of a thermostat is performed by temperature sensors (thermistors), which are checked by measuring resistance, but the classic ones remain the most common in the Biryusa line. Mechanical thermostats Before starting any work, be sure to disconnect the refrigerator from the power supply. Working with live electrical wiring is life-threatening. mechanical thermostats remain the most common in the Biryusa line.
Where to look for a thermostat: specific location in different models
The answer to the question where is the thermostat in the Biryusa refrigeratordepends on the year of manufacture and the specific modification of the device. In the vast majority of classic two-chamber models, such as series 118, 119, 133, 134, 145, 147, 148, 149, this element is located inside the refrigerator compartment. Usually it is hidden behind a plastic cover, in which a light lamp is also installed.
To access the unit, you need to open the door of the refrigerator compartment and pay attention to the upper right wall (if you look inside). There is a plastic box or control panel there. In some modifications, the temperature control knob is placed outside, on the front panel of the case, but the mechanism itself is still hidden inside the chamber behind the wall. This is done so that the sensitive element (bellows tube) is in contact with the evaporator or air inside the chamber, and not with the external environment.
In older or specific models, as well as in single-chamber refrigerators, the design may differ. Sometimes the thermostat is mounted directly on the evaporator, and to access it you have to remove the back panel inside the chamber or even get through the freezer compartment. However, for the popular line Biryusa with a bottom freezer, the standard is internal placement in the upper right corner of the refrigerator compartment.
It is important not to confuse the thermostat with other controls. If your model has a display or buttons on the outer door, this is an electronic control system, and there may not be a mechanical thermostat in the classical sense - its function is performed by sensors located at different points in the chamber. In such cases, troubleshooting requires a different technique based on measurements of the resistance of the sensors.
Step-by-step instructions for dismantling the thermostat
The process of removing the thermostat requires a minimal set of tools: usually a flat-head and Phillips screwdriver, as well as pliers, are sufficient. Before starting work, make sure that the unit is unplugged and remove all food from the refrigerator compartment so that they do not interfere with your view.
The first step is to remove the temperature control knob. It can simply pull towards itself or be held on by a screw hidden under a decorative plug. If the handle is removable, gently pull it, rocking it slightly from side to side. Be careful: the plastic becomes brittle over time and can crack from a strong tug.
Next you need to remove the plastic cover that hides the thermostat housing and the light bulb. Depending on the model of the Biryusa refrigerator, it can be attached with latches or screws.
- 🔍 Inspect the perimeter of the lining for visible screws, sometimes they are hidden under decorative caps.
- 🔍 If there are screws no, carefully pry the plastic panel with a flat-head screwdriver, starting from the bottom or side edge, to unclip the latches.
- 🔍 Remove the lamp shade if it interferes with access by first unscrewing the fixing screw or squeezing the latches.
- 🔍 Disconnect the wires going to the lamp and thermostat first remembering or photographing the connection diagram.
After removing the protective panel, you will see the thermostat itself - a metal or plastic block with suitable wires and a long copper or aluminum tube (bellows) coming out of it. The tube is usually secured to the evaporator using a special bracket or clamping bar. It is necessary to unscrew the tube fastening to release it.
☑️ Checklist before dismantling
The thermostat itself is attached to the body or bracket with screws or latches. Unscrew them and carefully remove the device. When pulling the bellows tube out of the hole in the chamber wall, proceed smoothly so as not to damage it or break the seal. If the tube is stuck or dirty, clean the outlet, but do not use excessive force.
⚠️ Attention: The thermostat bellows tube is very thin-walled. Any bend, puncture or severe deformation will lead to gas leakage and failure of the new part immediately after installation. Treat it like a fragile glass product.
Diagnostics and checking the performance of the part
Before you go to the store for a new spare part, you need to make sure that the problem is in the thermostat. The most reliable way to check is to use a multimeter in continuity mode. To do this, remove the terminals from the thermostat contacts and attach the tester probes to them.
At room temperature, the contacts of a working thermostat should be closed, and the multimeter will show zero or emit a beep. If the device shows a break (one on the screen or silence), it means that the contacts are oxidized or the mechanism is broken. To check for openness, you can place the thermostat sensing tube in a container of cold water (about 0°C) or apply ice to it. After some time, a click should be heard and the circuit will open.
The table below shows the main parameters for checking common models of thermostats used in Biryusa refrigerators:
| Thermostat model | Connection type | Temperature opening | Bellows length |
|---|---|---|---|
| TAM-133 | 3 contacts (+ ground) | -14...-23 °C | 0.75 m |
| K-59 L1175 | 2 contacts | -18...-24 °C | 0.75 m |
| TAM-145 | 3 contacts | -12...-20 °C | 0.9 m |
| K-57 L1150 | 2 contacts | -10...-18 °C | 0.6 m |
If you don’t have a multimeter at hand, you can use the exclusion method, but it is less accurate. For example, if the refrigerator does not turn on, you can briefly (literally 10-15 minutes to check) short the wires going to the thermostat, bypassing it. If the compressor starts and starts to freeze, then the thermostat is indeed faulty. However, this method requires caution: you cannot leave the refrigerator operating without a thermostat for a long time, since the compressor will work continuously and may burn or defrost the food.
Can I use a thermostat from another refrigerator?
Yes, you can often install an analogue. The main thing is that the mounting dimensions, the length of the bellows tube and the temperature range match. For example, instead of TAM-133, K-59 is often installed, but it may be necessary to adjust the temperature range with a screw on the case.
Replacing and adjusting a new thermostat
Installing a new one thermostat is done in the reverse order of dismantling. First, carefully guide the bellows tube through the hole in the chamber wall. Make sure it is not twisted or kinked. Secure the tube to the evaporator using a standard bracket or strip. The flat part of the tube must fit tightly to the surface of the evaporator for correct temperature reading.
Connect the wires to the contacts of the new regulator. It is critical here not to mix up the terminals. If you did not photograph the circuit, rely on the markings: usually wires with insulation of the same color are connected to the corresponding contacts, and the ground wire (yellow-green) is connected to the housing or a special contact. In two-pin thermostats, polarity is not important, but in three-pin thermostats (where the third wire goes to the lamp or indication), a connection error can lead to a short circuit.
After installing the mechanical part, adjustments must be made. The thermostat housing often has an adjustment screw hidden under a seal or plug. By rotating it, you can shift the operating temperature range. However, the factory setting is usually optimal for most conditions. If after installation the refrigerator begins to work incorrectly (does not turn off for too long), you can try to adjust the screw, but it is better to first check the tightness of the door and the condition of the seal.
Assemble the plastic cover, install the adjustment knob and turn on the refrigerator. Let it run for several hours to allow the temperature to stabilize. Check whether the compressor turns off when the desired temperature is reached and turns on when it heats up.
Common mistakes during self-repair
Repairing equipment yourself is always a risk of making a mistake, which can cost more than the services of a specialist. One of the most common mistakes is purchasing the wrong thermostat model. Visually, they may be similar, but differ in the length of the capillary tube or the temperature range of operation. Installing an unsuitable part will lead to incorrect operation: either the food will defrost or freeze.
Another common mistake is careless handling of the bellows tube during installation. Amateur craftsmen often try to push a long tube into a small hole by crushing it or bending it at an acute angle. This is guaranteed to cause damage. The tube should fit freely, without tension. If it is too long, it can be carefully twisted into a ring inside the chamber (if space allows), but not pinched.
Isolating the contacts is also often forgotten. After connecting the wires, you must make sure that the twists or terminals are securely insulated and do not touch the metal parts of the housing. In conditions of high humidity and vibration, poor insulation can lead to oxidation of the contacts or a short circuit to the housing, which is dangerous for the user.
Do not ignore the condition of the door seal when replacing the thermostat. If the door does not close tightly, heat constantly enters the chamber, and even a working thermostat will not be able to provide a normal temperature - the compressor will wear out. Therefore, once you have reached the insides, check and, if necessary, replace the sealing rubber.
Is it possible to temporarily do without a thermostat?
Technically, you can close the contacts to make the refrigerator work, but you cannot operate it in this mode for a long time. The compressor will work continuously, which will lead to freezing of the evaporator, spoilage of food and rapid failure of the motor. This is only a temporary diagnostic measure.
Which thermostat is better: TAM or K-59?
Both types are reliable. TAM (Russian-made) is often cheaper and more accessible, K-59 (European standard) is considered more accurate. The main thing is to choose an analogue with a suitable tube length and temperature range, and not a brand.
Why does the new thermostat click but does not turn on the compressor?
Perhaps the problem is not in the thermostat, but in the start relay, the compressor itself, or the wiring. It is also worth checking whether voltage is being supplied to the thermostat input terminals. If there is no voltage, you need to look for the cause earlier in the circuit.
Is it necessary to defrost the refrigerator before replacing it?
Yes, complete defrosting is required. This will allow you to safely work with electrical components, easily remove plastic covers, which become brittle in the cold, and correctly install the bellows tube on a dry evaporator.
How long does the thermostat in the Biryusa refrigerator last?
The average service life of a mechanical thermostat is 5-7 years of active use. However, with frequent power surges or temperature changes, it may fail earlier. Regular defrosting and cleaning prolong its life.