A sudden stop in the operation of the Stinol refrigerator is always stressful, because food supplies and the comfort of the whole family are at risk. Most often, the cause of the breakdown is the failure of the starting relay, which is responsible for starting the compressor motor. This small but critical element supplies voltage to the motor windings at the moment of switching on, and then opens the starting winding circuit.
If you notice that the motor hums but does not start, or, conversely, turns on for a few seconds and immediately clicks when turning off, the problem most likely lies in this node. Relay diagnostics does not require complex equipment and can be carried out at home, subject to basic safety measures. In this article we will analyze in detail the design of the mechanism, the symptoms of its breakdown and a step-by-step verification algorithm.
Before starting disassembly, it is important to understand that the Stinol refrigerator, like any other equipment, operates from a 220-volt power supply. Any manipulations with electrical components requires full unplugging the device from the outlet. Ignoring this rule may result in electric shock or damage to the electronics of the unit.
The principle of operation and the design of the starting relay
The starting relay in Stinol refrigerators, be it models 102, 103 or more modern series, performs the function of an automatic switch. When the compressor is turned on, the motor rotor is stationary, and to spin it up, a significant torque is required, which is created by the starting winding. The relay supplies current to this winding, and when the engine reaches the required speed (approximately 75% of the rated speed), the mechanism opens the circuit, leaving only the main winding to work.
There are two main types of such devices used in household appliances: electromagnetic (induction) and posistor (thermal). In older Stinol models, induction relays with a movable core and contacts that opened under the influence of gravity or a spring were more common. Modern units are equipped with positor relayswhere the role of a switch is performed by a ceramic element that changes its resistance when heated by current.
Structurally, the device is a plastic case, inside of which contacts, a coil (in electromagnetic models) or a posistor are placed, as well as a thermal relay for protection against overload. Thermal protection is a separate bimetallic element that opens the circuit if the current in the motor exceeds permissible values or if the compressor overheats. Combined operation of the starting and thermal relay ensures safe starting and operation of the motor.
⚠️ Attention: Internal structure the relay may differ depending on the compressor manufacturer (Danfoss, Aspera, Atlant) installed on your Stinol. Visually, they may be similar, but have different pinouts.
Understanding the principle of operation helps to quickly identify a fault. If the mechanism of sticking or burning of contacts is broken, the engine will not receive an impulse to start. If the problem is in the thermal relay, it will constantly turn off the power, protecting the motor from combustion, but preventing it from starting.
Main signs of a malfunction of the start relay
You can determine that the start relay has failed by characteristic sound and visual signs. Users often confuse a relay failure with a failure of the compressor itself, which leads to unnecessary expensive repairs. Let's look at the key symptoms that indicate a problem with the trigger mechanism.
The most common symptom is a characteristic click, followed by a humming sound from the compressor that lasts a few seconds, and a second click that turns off. This cycle can be repeated at intervals of 20-40 seconds. This behavior indicates that starting winding does not receive power or the mechanism cannot keep the contacts closed while the rotor accelerates.
- 🔊 Loud click: A sharp sound when trying to turn on, after which there is silence or buzzing.
- 🔥 Case heating: The compressor or rear grill of the refrigerator becomes hot, although no cold is produced.
- 💡 Flashing light: When the refrigerator starts, the light in the room may briefly dim due to a current surge.
- ❄️ Lack of cold: The chambers are gradually defrosting, since the compressor does not operate normally.
Sometimes the malfunction is accompanied by the smell of burning or melted plastic in the compressor area. This is a sure sign that a short circuit or overheating of the contacts has occurred inside the relay. In such cases operation of the refrigerator must be stopped immediately to avoid fire.
Preparation for diagnostics: tools and safety
Before you start checking the start relay of the Stinol refrigerator, you need to prepare a workplace and a minimum set of tools. High-quality diagnostics is impossible without visual inspection and the use of measuring instruments. You should not rely only on external signs, as they may be misleading.
First of all, you will need a multimeter (tester) to test the contacts and check the integrity of the windings. Pliers, a screwdriver (usually a Phillips or flathead screwdriver, depending on the housing model), and possibly contact cleaner will also be helpful. It is important to ensure good lighting of the working area, since the back of the refrigerator is often located in darkened niches.
☑️ Checking readiness for repair
It is extremely important to follow safety precautions. Even after disconnecting from the network, a residual charge may remain in the capacitors, although in household refrigerators it is small. However, the main rule remains to work only with a de-energized device. Electric current Invisible, but dangerous, so do not touch exposed wires with your hands.
It is also worth taking care of the safety of the floor covering and walls. When moving the refrigerator away, you may accidentally scratch the floor or damage the wallpaper. Cover the space behind the unit with cardboard or old rags. This is a small thing, but it will save you from unnecessary cleaning and possible conflicts with household members.
Dismantling and visual inspection of the relay
The process of removing the start relay on Stinol refrigerators is standardized, but requires care. The compressor is usually located at the lower rear of the unit and is covered by a metal or plastic casing. Removing the casing is the first step to diagnosis.
Unscrew the mounting bolts or remove the casing latches. You will see a view of the compressor - a black metal “tank”, to the shank of which a start relay is attached. It is usually closed with a plastic cap. To remove the relay, you need to carefully press the retaining tabs or remove the metal bracket that holds it to the compressor contacts.
After removing the device from its seat, carefully inspect its body. The presence of cracks, traces of soot, melting or swelling indicates a serious internal problem. Visual inspection allows you to screen out clearly faulty parts without the use of instruments. If the relay case has traces of thermal destruction, its restoration is impossible - only replacement.
What's inside the plastic case?
Inside the induction relay you will see a coil, a copper core and a movable contact group. In a posistor - a ceramic disk (posistor) and a bimetallic plate of a thermal relay. Often the contacts inside are covered with soot, which prevents the passage of current.
Pay attention to the condition of the wires going to the relay. They should not be brittle, have cracked insulation or oxidized contacts. If the wires are in order, you can proceed to a more in-depth check using a multimeter. Often the problem lies precisely in poor contact at the junction of the terminals.
Methods for checking a relay with a multimeter
The most accurate way to determine the performance of an element is to test the contacts using a multimeter. To do this, the device is switched to resistance (Ohm) or continuity measurement mode. If you have a posistor relay, the test will be slightly different from checking the electromagnetic analogue.
First of all, the thermal protection relay is checked. It should “ring” (show resistance close to zero) when cold. If the device shows infinity (one in the most significant digit), it means that the circuit is open and the relay is faulty. Also check the posistor itself: its resistance should be within 10-50 Ohms at room temperature.
For electromagnetic relays, it is important to check the mobility of the contacts. In a vertical position (as it stands on the compressor), the contacts of the starting winding should be open, and when turned over (simulating switching on), they should close with a click. The coil resistance is also checked by the tester - it should be finite, not infinite.
| Test type | Normal reading | Failure sign | Action |
|---|---|---|---|
| Thermal relay (cold) | 0 - 1 Ohm | Infinity (break) | Replacing the relay |
| Posistor | 10 - 50 Ohm | 0 Ohm or infinity | Replacing a posistor/relay |
| Contacts (closing) | 0 Ohm (ringing) | Infinity | Cleaning or replacing |
| Electromagnet coil | Final resistance | Infinity | Replacement relay |
If after checking it turns out that the relay is working properly, but the refrigerator does not work, the problem may lie deeper - in the compressor itself or the wiring. However, in 80% of cases, the described symptoms indicate precisely the unit being replaced. Posistor relays are disposable elements and cannot be repaired, only replaced.
Replacement and testing after repair
If diagnostics confirm a malfunction, you must purchase a new analogue. For Stinol refrigerators, universal relays or original spare parts from compressor manufacturers (Danfoss, Secop) are often suitable. When installing a new element, make sure that it sits tightly on the compressor contacts and is secured with a bracket.
Connect the wires in accordance with the color markings or the diagram photographed before disassembly. An error in the connection may result in a short circuit. After assembling all the elements and installing the casing, you can begin a test run.
Plug in the refrigerator. In the first seconds, you can hear a characteristic click and a smooth hum of the motor. This is a good sign. Note the operating time: the compressor must run for at least 10-15 minutes without shutting down before the thermostat breaks the circuit. If during this time there were no repeated shutdown clicks or the humming did not give way to silence, the repair was successful.
⚠️ Attention: Technical characteristics of compressors and relays may vary depending on the modification of the refrigerator. Always check the parameters of the new part with the markings on the nameplate of your unit or in the official documentation of the manufacturer.
Don't forget to check the heating of the compressor. Normally, it should be warm or hot (up to 70-80 degrees), but should not become hot to the point where it is impossible to touch it. Excessive heating may indicate improper operation of the cooling system or overload.
Frequently asked questions (FAQ)
Is it possible to temporarily start the refrigerator without relay?
Theoretically, you can start the compressor by applying voltage directly to the working and starting windings, but this is extremely dangerous and is not recommended. Without a thermal protection relay, the motor can burn out in a few minutes if it becomes jammed or overloaded. This is an emergency measure only for draining freon or diagnostics by a technician.
Why does a new relay burn out after a short time?
A common reason is a malfunction of the compressor itself (turn-to-turn short circuit of the windings), which consumes too much current, or problems with the voltage in the network. It is also possible that a relay with unsuitable current characteristics was selected.
Where can you find the relay markings on the Stinol refrigerator?
The markings are on the plastic body of the relay itself. To see it, you need to remove the protective cover at the bottom of the refrigerator. Look for a code like R600, PTM-R, or the manufacturer's catalog number.
Does the price of the relay differ greatly for different Stinol models?
The cost of starting relays for household refrigerators Stinol is usually low and varies depending on the type (positor or electromagnetic) and the manufacturer of the spare part. The difference in price between the models is insignificant compared to the cost of calling a technician.