Sudden stop of the compressor or a characteristic click, followed by a hum, but no cold appears - these are classic signs of failure of the starting device. For owners of Belarusian equipment Atlant the problem of replacement starting relay is one of the most common reasons for turning to specialists, although it can often be solved independently. Understanding the operating principle of this unit and the sequence of actions will allow you to save a significant amount on calling a specialist and restore the unit’s functionality in the shortest possible time.
The relay in refrigerators Atlant is responsible for starting the compressor engine, sending a short-term impulse to the starting winding. If this element burns out or its contacts stick, the motor hums, but cannot start, after which the thermal protection is triggered. Replacing the relay is a procedure that requires a minimum set of tools, but is critical for the safety of further operation of the electrical appliance. In this article we will analyze in detail the process of diagnosing, removing and installing a new component.
Before taking active steps, you need to make sure that the problem lies in the starting device, and not in the compressor itself or wiring. Users often confuse the symptoms, believing that the motor has failed, while the cost of replacing a small part is not comparable with repairing or replacing the compressor. The symptom is “buzzing for 5-10 seconds and clicking” in 85% cases indicates a malfunction of the starting relay or thermal protection. It is important to act consistently and follow safety precautions, since the work is carried out with electric current and refrigerant.
Diagnostics of a malfunction of the starting relay
The first step should always be visual and acoustic diagnostics. If the refrigerator Atlant stops freezing and the motor is silent or makes short humming sounds, this is a cause for concern. Pay attention to how the compressor behaves: if it turns on, hums for a few seconds and suddenly turns off with a characteristic click, most likely the starting winding is not receiving the required impulse. In this case, start relay does not perform its function of closing the circuit.
For more accurate diagnostics, you will need to remove the back cover at the bottom of the refrigerator and gain access to the compressor. By removing the casing from the starting device, you can remove the element itself. In older models Atlant RTK relays were often used, which can be checked by simply shaking them near the ear: if a ringing or knocking sound is heard inside, it means the mechanical part is damaged. More modern models have induction relays, which do not have moving parts in the classical sense, but are also susceptible to contact burnout.
- 🔌 Visual inspection: check the contacts for carbon deposits, plastic melting or wire oxidation.
- 👂 Acoustic test: light shaking of the part can reveal the destruction of internal elements (relevant for RTK).
- 🔍 Check with a multimeter:"continuity" of the contacts will show the presence or absence of an electrical circuit.
⚠️ Attention: Before removing any parts, be sure to disconnect the refrigerator from the power supply! Even briefly touching live parts can cause serious injury.
If a visual inspection reveals obvious signs of overheating or damage to the housing, further inspection may not be necessary - the part requires replacement. However, if the relay looks intact outwardly, it is worth checking its electrical parameters. Resistance between the contacts must correspond to the technical characteristics of a particular model. The absence of resistance or, conversely, a short circuit indicates that the device is faulty and will not be able to start the compressor.
Preparation of tools and selection of a new part
To successfully replace the relay, you do not need a complex professional tool. The entire process can be completed using a standard screwdriver and pliers. The main thing is to choose the right analogue of the failed part, since relays for compressors Atlant have different markings and are suitable for different types of engines. An incorrectly selected part may not start the motor or, worse, lead to its burnout due to a mismatch in current characteristics.
The body of the old relay is always marked, for example, RTK-1, R-1, R-3 or R-4. These symbols indicate the operating current and the type of switching. When purchasing a new spare part, be sure to check this information. It is also important to consider the orientation of the contacts: in some models Atlant the pins may be located at an angle or have different geometries, which will require care during installation.
The list of necessary tools is minimal, but each item is important for ease of work. Do not use damaged tools, as in the limited space behind the compressor it is easy to damage the insulation of the wires or break the threads of the fasteners.
- 🪛 Screwdriver: cross or flat, depending on the type of screws securing the casing.
- 🔧 Pliers: for carefully removing terminals and fixing wires.
- 🧤 Gloves: to protect your hands from sharp metal edges and possible oil contamination.
It is important to understand that there are no universal solutions. Although some craftsmen use so-called “universal relays”, for household appliances Atlant it is better to use original or certified analogues. This ensures consistent thermal and electrical performance, which will extend the life of the compressor. Saving on the cost of the relay can lead to expensive engine repairs.
Removing the old starting relay
The dismantling process begins with removing the protective casing that covers the compressor and the starting device. In refrigerators Atlant it is usually secured with latches or screws. Be careful not to use too much force to avoid breaking the plastic clips, which may become brittle over time. After removing the casing, you will have access to the lower part of the compressor, where the desired device is located.
The relay itself is placed directly on the three contact pins of the compressor. To remove it, you need to gently rock the device from side to side, while simultaneously pulling it towards you. Sometimes the contacts can “stick” or oxidize, which will require a little force, but do not jerk. A sudden movement can damage the ceramic base or tear off the wires suitable for the terminals.
☑️ Dismantling algorithm
After removing the relay from the compressor pins, you need to disconnect the wires. There are usually two or three of them, and they are fixed to the terminals. Remember or take a photo of which wire is connected where. In most cases, the color coding is standard, but it is better to double-check. If the wires are held in screw terminals, carefully loosen them with a screwdriver. If connectors are used, simply remove them with pliers.
⚠️ Attention: Do not pull on the wires themselves when removing the terminals! This can lead to a wire break inside the insulation, which will create problems when connecting a new part. Handle only the plastic or metal tip of the terminal.
Pay special attention to the condition of the pins on the compressor itself. If they are blackened or oxidized, they must be cleaned with fine sandpaper or a file until they have a metallic shine. Poor contact between the new relay and the compressor pins will lead to sparking and rapid failure of the new part. Clean contacts are the key to stable operation of the entire system.
Connection diagram and installation of a new relay
Installation of a new starting relay is carried out in the reverse order of dismantling. However, it is critical here not to confuse the polarity and purpose of the contacts. There is usually a marking on the body of the new relay and on the pins of the compressor: S (Start) - starting winding, R (Run) - working winding and common contact. An incorrect connection will result in the compressor either not starting or operating in emergency mode.
The table below shows standard contact markings for the most common types of relays used in refrigerators Atlant. Check with it before the final connection.
| Designation on the relay | Contact function | Wire color (standard) | Position on compressor |
|---|---|---|---|
C or L |
Common contact (Line) | Black or Red | Upper left |
S |
Start winding (Start) | Green or White | Upper right |
R |
Working winding (Run) | Blue or Yellow | Bottom |
After connection wires, put the relay on the pins of the compressor. It should fit tightly, without play. If the relay is not seated tightly, the contacts will heat up. Make sure that the device is in the correct orientation, usually indicated by an arrow UP or TOP on the case. For some relay models Atlant the position relative to the horizon is important for the thermal release to work correctly.
The final stage of installation is to install the protective casing and secure the wires so that they do not touch the hot parts of the compressor or moving elements (if there is a fan). The wires should lie freely, without tension. Only after a thorough check of all connections can you proceed with a test run.
Test launch and operation check
The first start after replacing the relay is the moment of truth. Plug in the refrigerator and listen. The compressor should start almost immediately, without prolonged buzzing or clicking. The sound of a running engine should be smooth and monotonous. If you hear the same symptoms as before the replacement (humming and clicking), then the problem is either an incorrect connection or the compressor itself is faulty.
Let the refrigerator operate for 15-20 minutes without loading food. During this time, check the heating of the new relay. It may be warm, but not hot. If the relay becomes so hot that it cannot be touched, turn off the device immediately. This may indicate a discrepancy in the current characteristics or poor contact at the junction of the pins.
- 🔊 Sound: even humming without vibration or clicking.
- 🌡️ Temperature: relay is warm, compressor is hot (within normal limits).
- ❄️ Cold: after 30-40 minutes the chamber should become noticeably colder.
⚠️ Attention: If after replacing the relay the compressor hums, but does not start for more than 3-5 seconds, immediately unplug the refrigerator! Long-term operation in this mode can (burn) the motor windings.
It is also worth checking the operation of the thermostat. When the temperature inside the chamber reaches the set value, the compressor should turn off. If it works without stopping, the problem may not only be with the relay, but also with a freon leak or a faulty temperature sensor. However, if the on-off cycle has been restored and cold has appeared, the replacement can be considered successful.
Common mistakes during replacement and expert advice
One of the most common mistakes is ignoring cleaning the compressor contacts. Installing a new relay on the oxidized pins negates all efforts. The oxides create resistance, causing heating and sparking. Always take the time to prepare your seating area. In addition, many people forget to check the integrity of the wires themselves, suitable for the relay, which could have frayed or melted during a previous malfunction.
Another mistake is using a relay with an inappropriate operating current. If you install a relay with a lower current, it will constantly click and turn off the motor. If it is large, it may not turn off the starting winding in time, which will lead to overheating of the engine. For refrigerators Atlant it is important to use parts recommended by the manufacturer for a specific series of compressors.
Is it possible to use a relay from another brand?
Technically, if the current characteristics and fit geometry are the same, relays from other brands (eg Danfoss or Secop) may be suitable. However, adapters and changing the connection diagram require in-depth knowledge of electrical engineering. For the home mechanic, the safest way is to look for an original analogue or a direct replacement with the same marking.
Do not forget that frequent relay replacements may be a symptom of a deeper problem. If the relays light up with enviable regularity, it is worth checking the voltage in the network. Voltage surges or too low voltage can cause unstable operation of the starter. In such cases, it is recommended to use a voltage stabilizer to protect all household appliances.
Why did the new relay immediately burn out after installation?
This can happen for several reasons: the compressor is jammed (the motor cannot turn over and takes a huge current), the type of relay is incorrectly selected (the cut-off current is not suitable), or there is a short circuit in the refrigerator's power supply system. It is also possible that during installation the contact was broken, causing sparking.
Where can I find the relay markings if they are erased?
If the markings on the housing are not readable, you will have to select an analogue according to the compressor model. Find the nameplate on the metal body of the motor itself (usually the manufacturer, for example, Atlant, and the model, for example, C-K 60 or C-K 100 are indicated there). Using this model, it is easy to find on the Internet the type of starting relay required.
Is it possible to repair an old relay rather than changing it?
Theoretically, the RTK relay can be disassembled, cleaned the contacts and reassembled. However, this is a temporary measure. The spring and mechanics inside are already tired, and the breakdown will happen again in the near future. Considering the low cost of a new part, repairing an old relay is not economically feasible and unsafe.
Does the tilt of the refrigerator affect the operation of the relay?
Yes, especially for a relay with a posistor or gravity-sensitive thermal protection. If the refrigerator is tilted too much, the mechanism may not work correctly. In addition, after transportation, the refrigerator must be allowed to stand for several hours before turning on, so that the oil flows into the compressor crankcase.
What to do if the compressor is hot, but does not start?
A hot compressor that does not start often indicates an interturn short circuit in the windings or a wedge in the mechanical part of the engine. If replacing the relay and checking the voltage did not help, most likely you will need to replace the compressor itself, which is a complex procedure that requires evacuation of the system and charging with freon.