Sudden stop of the compressor or characteristic Clicking sounds accompanied by a humming sound but no cooling often indicate a faulty starter. In Belarusian-made refrigerators Atlant this part is one of the most vulnerable elements of the electrical circuit. Starting relay is responsible for providing an impulse to start the motor and subsequent opening of the winding circuit, so its failure paralyzes the operation of the entire system.
Many equipment owners prefer to call a technician, but independent replacement is possible with a minimum set of tools and basic knowledge of electrical engineering. It is important to understand that incorrect installation or ignoring safety rules can lead to failure of an expensive compressor. In this material, we will analyze in detail the process of diagnosing and installing a new element.
Before starting work, you need to make sure that the problem lies in the relay, and not in the motor or wiring itself. Often the cause of breakdown is natural wear of the contacts or overheating of the bimetallic plate. It is critically important before installing a new part to check the compressor for an interturn short circuit, since installing a new relay on a faulty motor will lead to its instant combustion.
⚠️ Attention: All work on replacing electrical components must be carried out exclusively with disconnected from the power supply. Residual charge in the capacitors can lead to electric shock even after unplugging the device from the outlet.
Diagnostics of a faulty starter
The first sign of failure of the starter is the characteristic sound of a running engine, which abruptly ends with a click. The compressor tries to start, it hums for a few seconds, but then the protection opens the circuit and there is silence. If you touch the motor housing at this moment, it may be hot, which indicates attempts to start and overload of the windings.
For an accurate diagnosis, you need to remove the back panel of the refrigerator Atlant and gain access to the compressor. Visual inspection often helps to identify plastic melting or blackening of contacts, however, internal defects of the bimetallic plate are not always visible to the eye. Testing with a multimeter is the most reliable way to check the integrity of contacts in various positions.
There are several types relays installed on Atlant equipment, and their operating principle may differ. Some models use the electromagnetic principle, others use the thermal principle. Understanding the type of your part will help you correctly interpret the results of resistance measurements.
How to distinguish a working relay from a burnt one by ear?
When shaking a working relay of the RT (thermal) type, you can sometimes hear a slight knocking sound of the opening contact if it is in a cold state. If you hear a clear ringing of dangling parts inside or, conversely, complete silence with obvious signs of destruction, the part requires replacement. However, you cannot rely only on sound; instrumental control is necessary.
Necessary tools and preparation of the workplace
To successfully carry out repairs, you do not need complex professional equipment, a standard kit for a home handyman is sufficient. The main requirement is cleanliness and dryness in the work area, since moisture or metal shavings cannot enter the compressor. Before disassembling, clear the space around the back wall of the refrigerator.
You will need the following tools for dismantling and installation:
- 🔧 Screwdrivers (flat and Phillips) for removing the protective casing.
- 🔌 Multimeter to check the circuits and the new element.
- 🧤 Dielectric gloves for safety when working with wiring.
- 🧹 Soft brush for cleaning contacts from dust and oxides.
Special attention should be paid to the selection of a new part. On Atlant refrigerators, relays of the RT (thermal) and P-3 (electromagnetic) series are most often found. They are not always interchangeable, so when purchasing you need to focus on the marking of the old device or the model of the compressor. Compatibility is a key factor in the durability of the repair.
Removing the old one start relay
The process of removing the faulty part begins with disconnecting the refrigerator from the power supply. After this, the rear metal or plastic panel covering the motor-compressor is removed. It is usually attached to several bolts or latches, which require careful handling so as not to break the plastic, which has become brittle over time.
On the compressor housing you will see a plastic casing that covers the electrical part. It is fixed with a metal clamp or spring. Removing the clamp requires caution: pry it with a flat screwdriver and move it to the side, trying not to damage the copper tubes going to the motor.
After removing the casing, access to the relay and capacitor opens. The relay simply slides onto the three pins of the compressor and is wired to the capacitor. Carefully disconnect the wire block, having previously memorized or photographed the connection diagram, and remove the part from the contacts. Do not use excessive force to avoid breaking off the ceramic insulators.
⚠️ Attention: When dismantling, watch the position of the capacitor. If it is attached to the clamp along with the relay, it must be released separately. Sudden movements can lead to breakage of thin wires going to the terminals.
Algorithm for installing a new relay
Installation of a new element is carried out in the reverse order of dismantling, but requires attention to the orientation of the part. There is usually an arrow on the relay body indicating the direction UP or UP. This is a critical point: incorrect orientation will result in the mechanism not working or the contacts not closing.
Place the relay onto the three pins of the compressor, making sure it is seated tightly and all the way. Then connect the wires from the capacitor and the power plug to the appropriate sockets. Make sure that the terminals inserted with a characteristic click and are not loose. After this, return the metal clamp or spring that secures the casing to its place.
☑️ Check before turning on
The final stage of mechanical assembly is the installation of the protective casing and the rear panel of the refrigerator. Make sure the wires are not pinched or touching hot parts of the compressor. Only after complete assembly can you connect the unit to the network.
Compatibility and markings table
When selecting spare parts for the Atlant refrigerator, it is important to consider not only the brand, but also the type compressor. Different motor models require different starting characteristics. Below is a table to help you navigate the main types of relays found in this technology.
| Relay type | Marking | Application | Features |
|---|---|---|---|
| Thermal | RT-21, RT-23 | Atlant, Danifoss compressors | Overheat protection, noisy operation |
| Electromagnetic | R-3, R-4 | Powerful compressors | Requires precise orientation, quieter operation |
| Posistor | PTC (various) | Modern models | No moving parts, reliability |
| Combined | RTK, RTK-X | Old Atlant models | Combines starting and protection in one package |
If you are not sure about the choice, it is better to take the old part with you to the store or consult with a specialist, naming the compressor model stamped on its metal tag. Universal solutions there is practically no such thing in this area; experiments can be expensive.
First start-up and operation control
After installing the relay and assembling the refrigerator, the moment of exhaustion comes - the first start-up. Plug in the device and listen. The compressor should start after 1-3 minutes (protection delay time), producing a steady hum. The absence of clicks and buzzing without starting indicates the correct operation of the new part.
In the first hours of operation, it is recommended to periodically check the temperature of the relay housing and compressor. They may get hot, but should not be hot. If you smell a burning smell or hear a crackling sound, immediately unplug the refrigerator and re-diagnostics.
The normal operating mode is when the refrigerator gains temperature and turns off, and then the cycle repeats. If the motor runs continuously, the relay may be selected incorrectly or there is a freon leak in the system, which requires more serious intervention.
Frequent errors and ways to eliminate them
One of the common errors is ignoring condition of the capacitor. If the starting capacitor has lost capacity, the new relay will operate in extreme mode and quickly fail. Always check capacitor capacitance with a multimeter before installing a new set.
Another error is poor contact in the terminal block. Oxidized or loose contacts create additional resistance, causing heating and burning. Cleaning the contacts and tightly fitting the terminals is a must. Sometimes using a special conductive lubricant for contacts helps.
Do not forget about cleanliness. Dust collected in the compressor casing can cause overheating. Before installing the casing, it is recommended to blow out the space around the motor with compressed air or carefully clean it with a dry brush.
Is it possible to install a relay from another brand of refrigerator on Atlant?
Theoretically, this is possible if the electrical characteristics (operation current, type of windings) and mounting dimensions match. However, manufacturers often use unique connectors and housing shapes. It is better to look for original spare parts or high-quality analogues, specifically designed for compressors installed on Atlant equipment.
Why does a new relay burn out after a few days?
This indicates an underlying problem with the compressor. Possible reasons: interturn short circuit in the motor windings, jamming of the piston group or critical loss of freon, which is why the motor does not cool. In such cases, replacing the relay is only a temporary measure.
Do you need to wait after connecting to the network?
Yes, after connecting the refrigerator to the network, the compressor may not start immediately. The built-in thermal protection requires time (from 1 to 5 minutes) to cool down and restore contacts. This is a normal operating algorithm, and not a sign of a malfunction.
Is it dangerous to change the relay yourself?
If you follow electrical safety rules (mandatory disconnection from the network), the risk is minimal. The main danger is electric shock when the power is turned on or damage to the compressor tubes if the clamp is removed carelessly. If you are not confident in your abilities, it is better to entrust the work to a professional.
Where to find the markings of a suitable relay?
The markings are applied to the body of the part itself (often on the side or top) and on the compressor tag. Look for codes like RT-21, 3378, 117330. You can also find information in the technical documentation of the refrigerator or on specialized repair forums.