Double-chamber refrigerators Atlant are deservedly considered one of the most reliable units in the post-Soviet space, but even they are subject to wear and tear of electrical components. One of the most vulnerable points in these models is the start-up relay, which is responsible for starting the compressor and protecting it from overloads. If you notice that your refrigerator has stopped freezing, and the motor hums for only a few seconds and clicks, or is completely silent, there is a high probability that this particular part has failed.
Replacing a relay is one of the most affordable self-repair procedures that does not require deep knowledge in electronics or expensive special tools. Start relay is a small plastic block that is attached directly to the compressor housing. Its main function is to briefly supply current to the starting winding of the motor to start it up, and then turn it off when the motor reaches the required speed. In two-chamber models Atlant relays of series RT, RKT or LSare often used, which over time can burn out or stick.
Before proceeding with dismantling, it is important to make sure that the problem lies in the relay, and not in the compressor or wiring itself. The exact marking of the relay must match the original part or have identical electrical characteristics, since installing an unsuitable component can lead to failure of an expensive motor-compressor. In this article, we will analyze in detail the process of diagnosing, selecting and replacing the starting device so that you can bring your refrigerator back to life.
Diagnosis of a faulty starting device
The first sign of a faulty starting relay is the characteristic the sound of the refrigerator working. Instead of the smooth hum of a running motor, you hear a short hum, turning into a loud click, after which there is silence. This means that the engine is trying to start, but without the help of the relay, the starting winding does not receive the necessary impulse, and the thermal protection is triggered. If you put your hand on the side wall of the refrigerator, you can feel that the compressor vibrates slightly when it tries to start, but then cools down.
Sometimes the situation looks different: the refrigerator is silent, but the light is on inside, and you can hear the quiet hum of a transformer or timer. In this case, the relay could burn out completely, breaking the electrical circuit. To finally confirm the diagnosis, it is necessary to conduct a visual inspection of the part after removal. Often on the case starting relay traces of burning, plastic melting or blackening of the contacts are visible.
⚠️ Attention: If after replacing the relay the refrigerator does not start again or the machine in the panel knocks out, immediately stop trying to turn it on. This may indicate an interturn short circuit in the compressor windings, which requires calling a technician or replacing the unit itself.
It is also worth checking the condition of the wires going to the relay. In older models Atlant the insulation could dry out and the contacts could oxidize, which creates additional resistance and overheating. If you see carbon deposits on the terminals, they will need to be cleaned before installing a new component. Do not ignore the smell of burning in the compressor niche - this is a sure indicator of an electrical malfunction.
Preparing tools and selecting a new part
To successfully replace the relay, you will need a minimum set of tools that most men have in their homes. The main tool will be a flathead and Phillips screwdriver for removing the protective cover and loosening the clamps. You may also need pliers or side cutters if the wires are tightly secured or if you need to cut off old lugs. Fine-grained sandpaper for cleaning contacts will not be superfluous.
The most important step is purchasing the right one. start relay. Various types of compressors were installed on refrigerators (for example, Atlant Various types of compressors have been installed (e.g. Atlant, Secop/Danfoss, Embraco), and each type has its own relay. To avoid mistakes, remove the old part and look at its markings. It is usually applied to the side or top of the plastic case.
Main types of relays found in two-chamber refrigerators Atlant:
- 🔹 Relay series RT (RTK, RTK-1, RTK-1-3) - installed on old models with Atlant type compressors.
- 🔹 Series relays RKT - more modern analogues, often interchangeable with the series RT.
- 🔹 Series relays LS (LS-07B, LS-08B, etc.) - used with compressors Danfoss/Secop, have a slightly different housing shape.
- 🔹 Universal relays - may be suitable, but require precise selection of power and operating current.
When purchasing, pay attention not only to the model name, but also to the rated current. If you install a relay with a lower current, it will constantly turn off the motor. If it is too large, the compressor winding may burn out. The table below shows the main correspondences for popular models:
| Relay model | Compressor type | Rated current | Compatibility |
|---|---|---|---|
| RTK-1-3 | Atlant (old) | 1.3 A | MXM-1700, 1800 |
| RKT-25-1.2 | Atlant / Danfoss | 1.2 A | MXM-2800, 4000 |
| LS-07B | Danfoss / Secop | 2.7 A | MXM-6000 series |
| LS-08B | Danfoss / Secop | 3.2 A | MXM-7000 series |
Can a universal relay be used?
Universal relays (often included with adapters) can work, but their service life is usually lower than the original ones. It is recommended to look for an original or a high-quality analogue that exactly matches the marking.
Safety precautions and power outage
Working with electrical appliances requires strict adherence to safety rules. The refrigerator is a high-power energy consumer, and the compressor runs on 220 volts. Before starting any work, the unit must be completely de-energized. Simply turning off the button on the case is not enough, if there is one at all - you need to unplug the power cord from the outlet.
After unplugging, let the refrigerator stand for 5-10 minutes. This is necessary so that the refrigerant in the system has time to be redistributed and the pressure in the circuit is equalized. In addition, capacitors in the starting circuit may retain a residual charge that must dissipate. This is especially important for models with electronic control, although in mechanical Atlantakh the risk is minimal.
Provide access to the back wall of the refrigerator. Move the unit away from the wall at least 50–70 cm so that you can freely walk around it. Make sure the floor is dry and clean to prevent any slipping or dust getting into the machinery. If you are renovating the kitchen, cover the floor with newspapers or rags - dust and technical grease may spill out of the compressor compartment.
⚠️ Attention: Never touch the metal parts of the compressor or wires with wet hands. Even after disconnecting from the network, residual voltage or condensation can cause an unpleasant electric shock.
If you use an extension cord to connect a refrigerator after repair, make sure that its wire cross-section is designed for a current of at least 10–16 Amps. The use of thin household extension cords can lead to heating of the wires and a fire when the compressor starts, when the starting currents are maximum.
Removing the old starting relay
The process of removing the relay on two-chamber refrigerators Atlant is quite simple, but requires care. On the rear wall of the unit, in the lower part, there is a compressor (black metal “barrel”). A plastic box is attached to its end - this is the casing in which the relay and thermal protection are located. In some models Atlant the relay can be placed separately, but most often it is mounted directly on the compressor terminals.
First, remove the protective cover, if there is one. It can be secured with latches or screws. Proceed with caution as the plastic becomes brittle over time and may crack. Inside you will see wires going to the relay, and the part itself, put on three pins of the compressor. Before disconnecting the wires, it is strongly recommended to take a photo of the connection diagram so as not to mix up the contacts during assembly.
Dismantling procedure:
- 🛑 Disconnect the wires from the relay terminals (usually there are 2 or 3 of them). They can be held in place with a tight fit or secured with screws.
- 🛑 Remove the metal clamp bracket if it secures the relay to the compressor housing. It can be spring.
- 🛑 Gently rocking from side to side, pull the relay down from the compressor pins. Do not pull sharply to avoid damaging the tubes or terminals.
After removal, inspect the inside of the relay. There should be a copper core and a moving contact in the center. If you hear something dangling inside or see obvious traces of melting, the part is definitely faulty. Also check the condition of the terminals on the compressor itself: they should be clean and free of oxides.
☑️ Checklist before installation
Installing a new relay and assembling the system
Installing a new one start relay is carried out in the reverse order of dismantling. First of all, put the relay on the three pins of the compressor. It should fit tightly, with slight effort. Pay attention to the orientation: the relay housing and compressor often have an up/down or arrow marking to indicate the correct position. Incorrect orientation may result in the mechanism not working or operating intermittently. UP, indicating the correct position. Incorrect orientation may result in the mechanism not operating or operating intermittently.
After seating on the pins, secure the relay with a metal bracket-clip, if provided for in the design. Then connect the wires to the terminals. It is important here not to confuse phase, neutral and ground, although in most cases the relay operates regardless of polarity, with the exception of the ground wire (yellow-green), which always goes to the body. Use the diagram you photographed earlier.
If the terminals on the new relay do not match the old wires (different shape or diameter), you can carefully cut off the old tips and strip the ends of the wires. It is better to make the connection using terminal blocks or high-quality twisting followed by heat shrink insulation. Do not use regular electrical tape near heating elements, as the glue may leak.
After connecting all the wires, check the reliability of the connections again. Wiggle the relay - it should not wobble. Make sure that the wires do not touch hot compressor tubes or moving parts (although there are no moving parts on the outside of the compressor, vibration can wear down the insulation). Only after visual inspection can you proceed to a test run.
Test launch and operation control
The final stage is checking the functionality of the repaired refrigerator. Plug the power cord into a power outlet. In the first seconds you may hear a louder beep than usual - this is normal as the compressor is starting up after being idle. The relay should click (close the starting winding), the motor will start and switch to a smooth operating hum.
If the motor hums for 3-5 seconds, then a click is heard and it goes silent - the problem is not solved. This may mean that the new relay is also faulty, selected incorrectly (wrong current), or the problem is deeper (the compressor is stuck, the capacitor is faulty). In this case, repeat the diagnosis. If the compressor runs smoothly without turning off, proceed to temperature control.
Place the thermometer in the central part of the refrigerator 2-3 hours after startup. The temperature should drop to +4...+5 °C. In the freezer compartment of a two-chamber Atlanta temperature should reach -18 °C or lower within 24 hours. If the refrigerator gets cold, but does not turn off for a long time (more than an hour of continuous operation after reaching the temperature), it may be necessary to adjust the thermostat or check for freon leaks.
⚠️ Attention: In the first hours after repair, the compressor may work in increased mode. Do not load the refrigerator with food immediately - let it go into empty mode or with a minimum load.
Replace the protective cover of the compressor compartment and move the refrigerator to the wall, maintaining clearances for ventilation (at least 5 cm from the wall). At this point the replacement process can be considered complete. A correctly selected and installed relay will serve for years, restoring the full functionality of your refrigerator.
Frequently asked questions (FAQ)
Is it possible to replace the relay on the Atlant refrigerator universal?
Yes, there are universal starting relays that are suitable for many compressor models. However, for two-chamber Atlantov it is better to use specialized analogues (for example, RTK or LS), since they more accurately correspond to the current characteristics of the engine, which will extend the life of the compressor.
Why does a new relay burn out after a few days?
A common reason is incorrect selection of the operating current or a malfunction of the compressor itself (for example, difficult starting due to wear). Also, the relay can burn due to power surges in the network or poor contact in the terminals, causing sparking and heating.
Where can you find the relay markings if they are erased?
If the markings on the body are not readable, focus on the compressor model (indicated on the label next to it) and the refrigerator model. Using these data, you can select an analogue in spare parts catalogs for Atlant. You can also measure the resistance of the compressor windings for accurate selection.
Is it necessary to recharge the refrigerator after replacing the relay?
No, replacing the start relay does not violate the tightness of the refrigerant circuit. Freon remains inside the system, so additional charging or evacuation is not required. The repair is exclusively electrical.
How much does it cost to replace a relay in the compared to DIY service?
Independent replacement costs only the price of the part (usually 500–1500 rubles). In the service, the cost of the repairman and the visit will be added to the cost of the spare part, which can increase the amount by 2-3 times. If you have basic skills, self-repair is cost-effective.