Sudden shutdown of the compressor or endless operation of the Stinol refrigerator often indicates problems in the temperature control system. The main element that regulates turning the motor on and off is thermal relay, which can fail due to power surges or natural wear. If you notice that it has stopped freezing in the chamber, but the light is on, or, conversely, the food begins to freeze, the first thing you should suspect is this particular unit.
Diagnostics of the thermostat does not require complex equipment, just basic skills in working with tools and an understanding of electrical principles. In this article, we will look in detail at how to check the thermal relay of a Stinol refrigerator, what signs indicate its breakdown and whether it is possible to repair the device yourself. Stinol is a reliable technique, but even it has malfunctions that are easy to fix if you know where to look for the problem.
Signs of a malfunction thermostat in Stinol refrigerators
Before disassembling the unit, you need to make sure that the symptoms indicate the thermostat, and not a freon leak or a compressor breakdown. Thermostat is an electrical switch that opens the circuit when the set temperature is reached. If it “sticks” in the open state, the compressor simply will not receive a signal to start. In this case, it will be warm inside the chamber, and the motor itself will be silent.
The opposite situation, when the relay “sticks” in the closed state, leads to the refrigerator working without interruption. An ice crust forms in the chambers, the food freezes, and frost can be seen on the back wall. This mode of operation is dangerous due to overheating of the motor and increased energy consumption. It is important to distinguish these symptoms from problems with the door seal or a clogged capillary tube.
⚠️ Attention: If the compressor hums, but does not start, and after a while a click is heard and the hum stops, this may indicate not only the thermal relay, but also a malfunction of the start-up relay or the compressor itself. Do not rush to change the sensor until you have carried out a complete diagnosis.
Another sign is an incorrect response to turning the regulator knob. In good condition, when turning the knob from minimum to maximum, a characteristic click should be heard. If you turn the knob and there is no click, or it sounds in an arbitrary position, the mechanism is probably damaged.
Preparing for diagnostics: tools and safety
To conduct a quality check, you will need a minimum set of tools. The main device will be multimeter (tester), which allows you to ring the circuit for the presence of resistance. Without this device, accurate diagnosis is almost impossible, since visual inspection rarely shows internal defects in the contacts.
Also prepare screwdrivers (Phillips and flathead), pliers and, possibly, a knife for stripping contacts. Before starting any work, be sure to disconnect the refrigerator from the power supply. Working with live electrical components is strictly prohibited and can lead to electric shock.
Access to the thermostat in Stinol refrigerators is usually located inside the refrigerator compartment. You will need to remove the protective plastic cover that hides the temperature control knob. In some models, especially two-chamber ones with a system No Frost, the sensor may be located in a niche on the back wall or behind the control panel.
Visual inspection and initial check
After dismantling the plastic handle and removing the casing, carefully inspect the thermostat itself. Look for signs of oxidation, melted plastic, or soot on the terminals. If you see that the contacts are blackened or melted, this is a sure sign that a high current was passing through them, perhaps due to a poor contact or a power surge.
Check the condition of the bellows tube (capillary) that extends from the relay body. It should not have creases, cracks or signs of corrosion. Damage to this tube leads to the leakage of temperature-sensitive freon gas, causing the relay to stop responding to changes in temperature inside the chamber.
- 🔍 Inspect the contacts for the presence of a green oxidation deposit that prevents the passage of current.
- 🔌 Check the tightness of the terminals - they should not loosen or be easily removed with your fingers.
- 🌡️ Assess the condition of the corrugated cylinder - it should be intact, without dents or deformations.
Often the problem lies not in the relay itself, but in a broken wire that goes to it. Gently pull the wires at the base of the terminals. If the insulation is cracked or the wire is pulled out, the circuit will need to be repaired. However, if the device visually looks intact, we proceed to an instrumental check.
How to ring a thermostat with a multimeter
The most reliable way to check the serviceability of a thermostat is to measure the resistance of its contacts. To do this, switch the multimeter to continuity mode or resistance measurement mode (Ohms). Before testing, remove all wires from the thermostat terminals to exclude the influence of other elements of the Stinol refrigerator circuit on the device readings.
At room temperature, the contacts of most thermostats should be closed. Attach the multimeter leads to the appropriate terminals (usually terminals 3 and 4, or 3 and 6, depending on the markings). If the device shows “0” or makes a beep, the circuit is intact. If the screen shows “1” or “OL” (infinity), then there is a break inside and the relay is faulty.
☑️ Checking the thermal relay with a multimeter
For a more accurate diagnosis, you can conduct a test with a change in temperature. To do this, the thermostat must be removed from the refrigerator and placed in a cold environment (for example, in the freezer for 10-15 minutes). After cooling, the contacts should open and the multimeter should show an open circuit. If after freezing the contacts remain closed, it means that the mechanism is “stuck” and requires replacement.
It is important to consider that there are normally closed and normally open contacts. In Stinol refrigerators, normally closed ones at positive temperatures are most often used. If you confuse the terminals or the type of relay, the refrigerator either will not turn on or will not turn off.
Specific checks in models Stinol-103, 104, 107
Refrigerators series Stinol-103, 104 i 107 have their own design features. In these models, the thermostat is often located behind a plastic panel in the upper corner of the refrigerator compartment. To gain access, you need to unscrew the panel mounting screws and carefully unclip the latches so as not to damage the fragile plastic.
In two-chamber models with two compressors (for example, Stinol-104) two thermostats are used: one for the refrigerator compartment, the other for the freezer. If only one camera does not work, check the corresponding relay. In models with one compressor and system No Frost the thermostat can only control the refrigerator compartment, and a separate defrost sensor or timer is responsible for the freezer.
| Model Stinol | Relay location | Type of contacts | Feature |
|---|---|---|---|
| Stinol-101 | Inside the fridge compartment | Normally closed | Simple mechanics, easy to remove |
| Stinol-103 | Behind the panel in the corner | Normally closed | Long capillary tube |
| Stinol-107 | In the niche above the door | Combined | There is a quick freeze button |
| Stinol-104 | Two relays (top/bottom) | Different for cameras | Two independent circuits |
When replacing the thermostat in these models, pay attention to the length of the capillary tube. If the new part has a longer tube, it can be carefully twisted into a ring and placed inside the case, but in no case cut it or bend it at an acute angle.
Replacing the thermostat: step-by-step algorithm
If the diagnostics showed a malfunction, the only correct solution is to replace the unit. Repairing the internal mechanisms of the thermal relay is impossible due to their tightness and precise calibration. Buy an analogue that fully matches the markings of your old relay (for example TAM-133, K-59 or RANCO).
First, dismantle the old relay by disconnecting the wires and carefully pulling the sensitive tube out of the evaporator. Install a new thermostat, securing it in the seat. Connect the wires according to the diagram that you photographed earlier. Pay special attention grounding, if it is provided by the design (usually this is a wire going to the case).
⚠️ Attention: The sensitive tube of the thermal relay is very thin and is easily damaged. When installing a new relay, do not apply excessive force and do not bend the tube with a radius of less than 5 cm, otherwise the gas inside it will escape and the relay will stop working.
After assembly, turn on the refrigerator. For the first few hours, it can work in intensive mode, increasing the temperature. Do not load the chamber with food immediately, let the equipment enter the operating cycle. Check whether the compressor turns off after reaching cold.
Common mistakes during self-repair
One of the common mistakes is ignoring the markings. contacts. On different relay models, the numbers may mean different purposes. For example, terminal “6” on one relay may be a ground, and on the other - a contact for a lamp. Always check the diagram of the specific device.
Another mistake is trying to “develop” a stuck mechanism by tapping or rotating the handle with force. This can lead to the final destruction of the plastic gears inside the case. clicks, it is better to replace it immediately than to waste time on resuscitation.
Is it possible to use a universal thermal relay?
Universal relays (for example, with an adjustable tube length) often require adjustment. They can be used as a temporary solution, but for long service it is better to install the original or a complete analogue in terms of characteristics.
Some technicians advise shorting the contacts to make the refrigerator work. This is absolutely forbidden! In this mode, the compressor will operate continuously, which will lead to overheating, freezing of the evaporator and spoilage of food. This is only permissible for a short-term check of the compressor, but not for operation.
Questions and Answers (FAQ)
Is it possible to check a thermal relay without a multimeter?
It is impossible to check accurately. You can only visually assess the condition or make a temporary jumper to check the operation of the compressor, but this will not guarantee the serviceability of the relay itself when the temperature changes.
Why does the new relay fail? does it click?
The new relay may not click immediately if the temperature in the chamber has not yet reached the shutdown threshold. It is also possible that the relay model is not suitable or the contacts are incorrectly connected. Let the refrigerator operate for 20-30 minutes.
Where can I find the markings for the Stinol thermal relay?
The marking is applied to the metal body of the device. To see it, you often have to remove the plastic casing and sometimes even remove the relay from its seat. Popular brands: Danfoss, Ranco, Klixon.
How much does it cost to replace a thermal relay?
The cost of the relay itself varies from 800 to 2000 rubles depending on the model. The services of a replacement specialist will cost an additional 1500-3000 rubles. Self-replacement saves the budget, but requires care.
What to do if the capillary tube of the new relay is longer?
The excess length of the tube can be carefully rolled into a ring with a diameter of at least 4-5 cm. and place it in the free space inside the refrigerator body. The main thing is not to break the tube or damage it with a sharp tool.