Sudden stoppage of the compressor is one of the most common and unpleasant situations faced by owners of household appliances. When the refrigerator Stinol stops freezing, and the motor is either silent or makes only a short click and hums for a couple of seconds, in 80% of cases the culprit is the start-up relay. This small but critical element is responsible for starting the motor and protecting it from overheating.
Diagnostics of this part does not require complex equipment, but requires care and understanding of the operating principle of the electrical circuit. Start relay provides voltage to the starting winding of the engine at the moment of start, and then turns it off. If this mechanism is broken, the compressor cannot start or operates in emergency mode, which can lead to expensive repairs of the entire refrigeration system.
Before calling a technician or buying a new compressor, it is necessary to eliminate the possibility of a simple relay failure. Often the problem is solved by replacing an inexpensive component, which you can do yourself if you have basic tools. In this article we will look in detail at how to identify a malfunction, what tools will be needed and what to look for when diagnosing models Stinol 101, Stinol 103 and other popular modifications.
⚠️ Attention: All work on diagnosing and replacing electrical components should be carried out exclusively with the power supply disconnected from the network. Failure to follow safety rules can lead to electric shock.
The operating principle and signs of a relay malfunction
In order to carry out quality diagnostics, you need to understand exactly how the device functions. In refrigerators Stinol most often posistor or induction relays are used. When the compressor is turned on, a high starting current passes through the winding, which heats the posistor (thermistor). Resistance The posistor increases sharply, and the starting winding circuit opens, allowing the engine to operate normally on one working winding.
If the mechanism sticking contacts are broken or the posistor is broken, the engine does not receive the necessary impulse to start. A characteristic sign of a malfunction is a cyclic repetition of startup attempts: you hear a click, the motor hums for 3-5 seconds, then a second shutdown click is heard, and there is silence for several minutes. This cycle is repeated until the thermal protection trips or the winding burns out.
Visual inspection can also provide the first answers. If traces of burning, melting of plastic or soot are visible on the relay body, the part definitely requires replacement. However, the absence of external defects does not guarantee serviceability, so it is necessary to carry out an instrumental check. The critical parameter is the integrity of the contacts and the resistance of the posistor, which in a cold state should be only a few Ohms.
- 🔊 Clicks: A loud click when turned on and a second click after a few seconds without starting the motor.
- 🌡️ Heating: Strong heating of the relay housing or the lower part of the compressor during short periods of operation.
- 🔌 Lack of cold: The compressor does not start at all, although the light in the refrigerator is on.
- 💥 Knocking out plugs: Short a short circuit inside the relay can lead to the operation of the circuit breakers in the panel.
Necessary tools and preparation for diagnostics
To carry out a quality test, you will need a minimum set of tools, which most home craftsmen can find. The main device will be multimeter (tester), capable of measuring resistance in the range from 0 to 20 kOhm and checking the integrity of the circuit. Without this device, diagnostics will be only tentative.
You will also need pliers, a screwdriver (Phillips and flat) to remove the protective covers and, possibly, a knife for stripping the contacts if you plan to restore them (although for Stinol relays a complete replacement is often recommended). Before starting work, the refrigerator must be defrosted, if there is ice on the evaporator, and moved away from the wall to access the rear panel.
The preparation process includes completely de-energizing the unit. Remove the plug from the socket and wait 10-15 minutes for the residual voltage in the circuits to dissipate and the compressor to cool down. This is important, since the thermal relay may be in an open state due to heating, and a cold test will give a false result.
☑️ Preparing to test the relay
Removing the start relay from the compressor
Access to the relay in refrigerators Stinol usually located in the lower rear parts of the housing where the compressor is located. The black casing that covers the motor must be removed by unscrewing the mounting screws or releasing the latches. On the side or top of the compressor you will see a plastic box - this is the unit you are looking for.
Remove the relay carefully so as not to damage the suitable wires. It is usually fixed on three contacts coming out of the compressor, and is additionally held in place by a tight fit or a metal bracket. If the design includes a bracket, it must be pressed out with pliers. In some models Stinol 104 or Stinol 116 it may be necessary to remove the clamp holding the wires.
After removing the device, inspect the connectors. Contacts must be clean and free of oxidation. If you find green deposits or rust, you can carefully clean them off, but most often oxidation indicates moisture ingress, which could cause the part to fail. The markings on the case will help you choose an exact replacement.
⚠️ Attention: When dismantling, do not apply excessive force to the wires. Old insulation can be fragile, and an accidental break will require extension of wires and additional insulation.
Method of testing with a multimeter: step-by-step instructions
The most reliable way to test is to use a multimeter in resistance measurement mode (Ohm). Switch the device to the 200 ohm or 2 kohm position. First, let's check the circuit between the contacts responsible for the starting winding. Insert the probes into the corresponding relay sockets.
If you have a posistor relay in your hands (the most common for Stinol), in a cold state the resistance between the main contacts should be low, usually in the range of 5-50 Ohms. If the device shows one (infinity) or zero, then the posistor is faulty. A short circuit (0 Ohm) indicates a breakdown, and infinity indicates a break.
Next, we check the thermal protection if it is built into the relay housing (often in prefabricated blocks). Ring the contacts of the thermal relay: in a cold state the circuit should ring (resistance is close to zero). Heat the relay with a hair dryer or hold it in your hands - after a while the circuit should break, which indicates the serviceability of the thermal protection.
What to do if you don’t have a multimeter at hand?
If you don’t have a tester at hand, you can assemble a simple “control” from a 12-24V light bulb and a battery. However, this method is less accurate and will not show the exact resistance of the posistor, but will only indicate the presence or absence of an open circuit. For refrigerator relays, this method is considered not reliable enough.
Table of typical resistance values for different models
Different modifications of compressors and relays may have different technical characteristics. Below is a table with approximate values that are considered the norm for serviceable parts installed in refrigerators Stinol.
| Relay type / Model | PTC resistor resistance (cold) | Thermal protection resistance | Status circuit |
|---|---|---|---|
| RTK-1 (Analog) | 15 - 25 Ohm | 0.1 - 0.5 Ohm | Closed |
| PTC 1204 (Stinol) | 20 - 40 Ohm | 0.1 - 0.5 Ohm | Closed |
| DR-120-01 | 10 - 20 Ohm | 0.2 - 0.6 Ohm | Closed |
| Faulty posistor | Infinity (∞) | Any | Broken |
| Broken posistor | 0 Ohm | Any | Short-circuited |
If your measurements differ radically from the table values, the part must be replaced. Remember that even a slight deviation in the resistance of the posistor can lead to the fact that it does not have time to warm up and turn off the starting winding, which will cause the motor to overheat.
Replacing the part and checking the functionality systems
After confirming the malfunction, the old relay must be replaced with a new one. When purchasing, pay attention not only to the markings, but also to the orientation of the contacts. The relays are placed on the compressor contacts in a certain position, usually marked as UP (top) or an arrow.
Install the new device by firmly placing it on the three pins of the compressor. Make sure it is secured in place (with a bracket or latches). Connect the wires according to the diagram, which is often marked on the compressor cover or on the relay body itself. You can’t mix up the wires - they have different colors and diameters, but it doesn’t hurt to double-check visually.
Plug in the refrigerator. A working unit should start with a characteristic hum, which after 10-15 seconds will become quieter and smoother. This means that the starting winding has turned off and the motor has entered operating mode. Check the heating of the new relay case after 20-30 minutes of operation - it may be warm, but not hot.
Frequent diagnostic mistakes and expert advice
One of the common mistakes is trying to clean the contacts inside the sealed case of a posistor relay. Unlike old induction models, modern positors cannot be repaired - their internal structure irreversibly changes when overheated. An attempt to “revive” such a part will only lead to repeated failure after a short time.
Also, technicians often forget to check the compressor itself. If, after replacing the relay, the engine hums but does not start, or starts and immediately stalls, the problem may be a jammed piston or an interturn short circuit in the motor windings. In this case, the relay has nothing to do with it, and more serious repairs are required.
Use only original spare parts or high-quality analogues recommended by the manufacturer Stinol. Cheap Chinese analogues may have an inadequate PTC response time, which will lead to frequent on-off cycles and shorten the life of the compressor.
Is it possible to start a Stinol refrigerator without a starting relay?
Theoretically, you can start the engine by applying voltage directly to the starting winding, but doing this is strictly prohibited in domestic conditions. This requires precise calculation of the timing of the pulse and threatens breakdown of the windings or fire. Without a relay, the compressor will not work for a long time.
Why does a new relay burn out after a few days?
A common reason is unstable voltage in the network or a malfunction of the compressor itself (turn-to-turn short circuit), which consumes increased current. It is also possible that a relay with unsuitable resistance characteristics was selected.
Where can you find the relay markings on a Stinol refrigerator?
The markings are applied to the side or top edge of the plastic relay case. Reading the label often requires removing the part from the compressor casing. Look for codes like PTC, RTK or digital designations.
How much does it cost to check a relay at a service center?
Diagnostics at a service center usually costs less than a replacement, but given the ease of checking with a multimeter, it is often more profitable to call a technician immediately with a new part, so as not to pay twice for a visit.