Finding the place where it is starting relaybecomes critically important when the refrigerator stops cooling or makes loud clicks. Typically this device is attached directly to the motor-compressor housing, which is located at the lower rear of the unit. You can get to it only by moving the refrigerator away from the wall and removing the protective rear panel covering the engine compartment.
The appearance of this element resembles a small plastic barrel of black or white color, to which the wiring harness fits. It is through this unit that voltage is supplied to the motor windings, starting the process of refrigerant compression. If you hear the motor trying to start, humming for a couple of seconds and abruptly turning off with a characteristic click, then the problem most likely lies in this component.
It is important to understand that the exact location may vary slightly depending on the manufacturer, be it Indesit, LG or Atlant. However, the general layout of components in household refrigerators has been standardized for years, so the algorithm for troubleshooting will be almost identical for most models. The main thing is to follow safety precautions and turn off the power to the device before starting any manipulations.
Location of the unit depending on the type of compressor
Before looking for where the refrigerator compressor relay is located, it is worth checking the type of engine installed. In classic models with a conventional piston compressor, the required element is always in conjunction with a protection thermostat. They form a single block that fits directly onto three contact pins protruding from the side or bottom of the motor housing.
The situation changes dramatically if your unit has inverter compressorinstalled. In such systems, often found in models Samsung or LG the latest generation, there may not be a classic starting relay in the usual sense. Its function is performed by an electronic control board, which can be located separately, for example, in the upper part of the refrigerator or in a niche under the freezer.
Inverter systems are characterized by the absence of mechanical clicks at start-up. If your refrigerator runs quietly and then just goes silent without a characteristic shutdown sound, you should not look for a mechanical relay, but check the electronics. Visually, inverter motors often have a closed casing, and access to the contacts is limited.
You can determine the type of compressor by the markings on the nameplate located on the motor housing. It will indicate the voltage, refrigerant type and model. If you see the words “Inverter” or the rotation speed in hertz, then searching for a mechanical relay in the engine compartment will be futile.
⚠️ Attention: Inverter systems are sensitive to voltage fluctuations. An attempt to replace the standard starting device from a conventional refrigerator with an inverter unit will lead to instantaneous combustion of expensive electronics.
Step-by-step instructions: how to get to the relay
To find and inspect the relay, you will have to perform a series of sequential actions. The process does not require complex tools, but does require care, since the plastic fasteners of old refrigerators can be fragile.
First, you need to completely turn off the power to the appliance by unplugging the plug from the socket. Then move the refrigerator away from the wall, giving you easy access to the back wall. In most cases, the compressor is covered with a metal or cardboard cover, which is secured with bolts or latches.
Use a Phillips screwdriver or screwdriver to remove the fasteners. If the lid is cardboard and is held on by latches, carefully pry them off with a flat object. After removing the cover, you will have a view of the motor, condenser grille and tube system.
☑️ Preparation for access
Find a black cylindrical tank - this is the compressor. A bundle of wires coming into a plastic box approaches it from the side or below. This is the node we are looking for. In some models, for example, in old ZIL or Biryusa, the relay can be placed separately on the chamber wall, but this is rare for modern technology.
To remove the device, you must first disconnect terminal block with wires. It may be a tight fit, so rock it slightly from side to side. Then carefully remove the plastic box itself from the compressor contact pins. It is often fixed with a metal clamp that needs to be released.
Visual diagnostics and signs of malfunction
After you have removed the device from its seat, it must be carefully inspected. Start relay is an electromechanical device, and its breakdowns often have visual manifestations. Shake the part near your ear: if a distinct knocking or ringing is heard inside, it means that the core or contacts have fallen apart, and the part requires replacement.
Inspect the plastic case for melting, blackening or burning marks. If you see black streaks or smell burning plastic, this is a sure sign of a short circuit inside the assembly. Also pay attention to the condition of the contact pads: they must be clean, free of oxides and carbon deposits.
Inside the case there is a coil and a movable core. When the coil heats up, the core should rise and open the circuit. If the mechanism is stuck in the down position, the compressor will hum, but will not start until the thermal protection is triggered.
| Symptom | Probable cause | Action |
|---|---|---|
| Loud clicking and silence | Relay coil burnt out | Replace part |
| Humming for 5-10 seconds and shutting down | Contacts sticking or motor jamming | Checking the compressor |
| The refrigerator does not turn on | Open circuit in the relay | Continuity test with a multimeter |
| Burning smell in the engine compartment | Short circuit | Urgent replacement |
Why does the relay burn out?
A frequent cause of failure is not only natural wear and tear, but also unstable voltage in the network. Voltage surges lead to overheating of the coil and welding of the contacts. Also, the problem may lie in the compressor itself: if it is difficult for the motor to turn over (bearing wear, lack of freon), starting currents increase and the relay burns out trying to start the unit.>
Technical check with a multimeter
Visual inspection does not always give a 100% guarantee. To accurately verify the malfunction, where the refrigerator compressor relay is located is already known, now you need to pick up a tester. Switch the multimeter to resistance measurement mode (Ohms).
Ring the main contacts. In a normally closed state, the resistance between certain pairs of contacts should be close to zero. If the device shows one or infinity where there should be a circuit, then there is a break inside.
Pay special attention to the thermal protection relay, which is often built into the same housing or adjacent to it. It is a bimetallic plate. When cold it should ring. If the circuit is open to a cold part, the thermal fuse has burned out.
Checking the inductor is also important. The winding resistance is usually several tens of ohms. If the resistance is too high or zero (short circuit), the part is unsuitable for use.
⚠️ Attention: Do not test under voltage! All manipulations with the multimeter are performed only with the device completely disconnected from the network and removed from the compressor.
Nuances of replacement and selection of analogs
When you have determined that starting relay it is faulty, it must be replaced. The main principle of selection is complete matching of markings. Numbers and letters are stamped on the body of the part, for example, “RTK-1”, “R600a” or “1500”. Ignoring these designations may result in the new element not being suitable in terms of fitment dimensions or current characteristics.
Different manufacturers, such as Danfoss, Secop or Atlant, may use different types of fasteners. Somewhere the relay is put on top, somewhere on the side. Orientation is also important: some parts have an "UP" or "UP" arrow indicating how to correctly install the device relative to the axis of the compressor.
When installing a new element, make sure that the compressor contact studs are clean and not oxidized. If they have deposits on them, carefully sand them off with fine sandpaper or a file. Poor contact will lead to heating and rapid failure of even a new part.
Assembly is carried out in the reverse order: first we put the relay on the studs until a characteristic click is heard, then we connect the terminal block with wires. It is important that the wires do not touch the hot compressor housing or tubes, otherwise the insulation will melt.
Frequently asked questions and answers
Is it possible to start a refrigerator without a relay?
Theoretically, you can start the motor by applying voltage directly to the starting and working windings, but doing this is strictly prohibited in domestic conditions. Without a protective relay, the compressor will burn out in a few seconds due to lack of overload protection, or a short circuit will occur.
Why is the second relay burning out in a month?
If the relay is replaced regularly, the problem lies not in the part itself, but in the compressor. The motor may be “difficult” to start due to exhaustion of the mechanical part or problems with freon. In this case, the relay constantly operates in overload mode.
Where is the relay located in No Frost refrigerators?
In No Frost systems, the location is standard - in the rear engine compartment. However, in such models there is often an additional defrost relay, which is located inside the freezer, behind the rear panel, next to the evaporator heater.
How much does it cost to replace the relay?
The cost of the part itself varies from 500 to 2000 rubles, depending on the model of the refrigerator and the manufacturer of the spare part. The work of a replacement technician usually costs from 1000 to 2500 rubles, although the process takes no more than 20 minutes.
Is it possible to repair an old relay?
Repair is possible only if the contacts are heavily soiled. If the coil burns out or the core is deformed, it is impossible to restore functionality. Considering the low cost of new analogues, repairing an old device is not economically feasible.