A sudden stop of the refrigerator compressor Atlant often becomes an unpleasant surprise, especially when there are perishable foods left inside. In most cases, the cause of the breakdown is the failure of the starting relay, which is responsible for starting the engine. Starting relay is a key element of the electrical circuit that provides a short-term voltage supply to the starting winding of the motor.
Replacing this component yourself is a real task for a home craftsman who has basic skills in working with tools. However, before you start disassembling, you need to make sure that the diagnosis is correct so as not to waste time and money on serviceable parts. Atlant refrigerators equipped with different types of engines, and understanding their features will help avoid installation errors.
In this article we will analyze in detail the process of diagnostics, selection and installation of a new relay. You will learn how to correctly connect the contacts, what to look for when inspecting an old device, and what safety measures are required when working with electrical appliances under voltage.
Diagnostics of a faulty start-up relay
Before proceeding with replacement, it is important to determine exactly what the problem lies in the relay. Users often confuse a breakdown of the starter with a malfunction of the compressor or thermostat itself. The main sign of relay failure is a characteristic click, which is heard every few seconds or minutes, while the compressor itself does not start or hums only for a moment.
If, when you turn on the refrigerator, the motor tries to start, makes a humming sound and immediately turns off, this is a sure sign that the starting winding does not receive the required impulse. It is also worth paying attention to external signs: a melted relay body, a burning smell or blackened contacts indicate overheating and a short circuit inside the device.
For more accurate diagnostics, you can use a multimeter. By ringing the contacts of the inductor and thermal contacts, you can identify a break or short circuit. If the coil resistance is infinitely high or, conversely, equal to zero, the part must be unconditionally replaced.
⚠️ Attention: If after replacing the relay the compressor continues to hum and does not start, the motor itself may be jammed or the problem is in the capacitor. In this case, further independent diagnostics without special equipment can be dangerous.
Types of relays used in Atlant refrigerators
The manufacturer Atlant in different years of production and in different series of refrigerators used various modifications of starting devices. Understanding the differences between them is critical, since visually similar parts may have different electrical circuits and operating principles. The main division occurs into induction (electromagnetic) and posistor (thermal) relays.
Induction relays, often labeled as RTP or RTK, operate on the basis of an electromagnetic field. When current is applied, the coil core is retracted, closing the contacts of the starting winding. After the motor rotor accelerates, the current drops, and the core, under the influence of gravity, returns to its original position, opening the circuit. Such devices are position sensitive - they only work in a certain orientation.
Posistor relays, known as PT (thermal), take advantage of the property of the posistor to sharply increase resistance when heated. When turned on, a cold posistor passes current, starting the motor, then heats up and actually breaks the starting winding circuit. They are less demanding in terms of spatial position, but have a time delay for cooling before restarting.
What is the difference between RTP and RT?
RTP (Current Start Relay) - electromagnetic, requires strict downward arrow orientation. RT (Thermal Relay) - uses a posistor, is less sensitive to position, but requires cooling time (3-5 minutes) between switching on.
Required tools and safety measures
Working with electrical equipment requires compliance with strict safety rules. Any manipulations with the internal components of the refrigerator should be carried out only after completely disconnecting the device from the electrical network. Voltage 220 volts poses a real threat to life, so this rule absolutely cannot be neglected.
To carry out the work you will need a minimum set of tools. The main tool will be a screwdriver (often a Phillips or flat-head screwdriver, depending on the casing fastener). You may also need pliers for removing clamps or terminals and a multimeter for checking circuits.
- 🔌 A screwdriver with a dielectric handle for safely unscrewing screws.
- 🧤 Dielectric gloves for additional protection when working with wires.
- 📱 A smartphone with a camera for photographing the connection diagram before disassembly.
- 🧹 Dry rags for cleaning contacts from dust and oxides.
Particular attention should be paid to the condition of the wire insulation. If you find frayed areas or cracks in the insulation, they must be repaired using electrical tape or heat shrink before connecting a new relay. Working with exposed wires is unacceptable.
☑️ Safety check before starting work
Step-by-step instructions for replacing the relay
The replacement process begins with access to the compressor. In refrigerators Atlant the compressor is usually located at the lower rear of the unit. It is necessary to move the refrigerator away from the wall, providing easy access to the rear panel. On some models, it may be necessary to remove the metal casing covering the engine compartment.
Locate the start relay, which is placed directly on the side or bottom terminal of the compressor. It comes in a black or white plastic box. Carefully remove the retaining bracket or bend the spring clips holding the relay to the motor housing. Be careful not to damage the associated wires.
Remove the old relay by pulling it down or to the side (depending on model). Before disconnecting the wires, be sure to photograph the location of the terminals. This will help avoid errors when connecting a new device. Disconnect the block with wires from the relay.
⚠️ Attention: When removing the old relay, make sure that moisture or foreign objects do not get inside the compressor through the open contact holes.
Install the new relay in strict accordance with the markings. There is usually an arrow on the body of the device indicating the direction "UP" (up) or "DOWN" (down). Incorrect orientation will result in the relay armature not being able to return to its original position under the influence of gravity, and the engine will not start.
Connect the terminal block with wires to the new relay until it clicks. Make sure that the wires are not stretched or touching hot parts of the compressor or sharp metal edges. Fix the relay on the compressor terminals and install the protective casing in place.
Connection diagram and contact marking
Correct connection of wires is the key to successful repair. Refrigerators Atlant most often use standard color markings, but you should not rely on color alone, since over the years of operation the wires could have been resoldered by previous technicians. The main contacts are common, starting and working.
Usually three main wires go to the relay: phase (often black or brown) coming from the thermostat, and two wires going to the compressor windings. Some circuits also have a ground wire. It is important not to confuse the contacts of the starting and working windings, otherwise the engine will hum, but will not start, which can lead to its combustion.
Below is a table of contact correspondence for common types of relays used in Atlant technology:
| Contact type | Designation on diagram | Wire color (standard) | Function |
|---|---|---|---|
| Common | C or COM | Black / Brown | Power supply from the thermostat |
| Start | S | Red / Pink | Engine start (short-term) |
| Working (Run) | R | White / Green | Main engine operation |
| Grounding | PE | Yellow-green | Protection from electric shock |
If the colors of the wires in your refrigerator differ from the standard ones, use a multimeter in test mode. The resistance between the common contact and the starting contact is usually higher than between the common and working contacts. You can also use the location of the pins on the compressor itself as a guide: they form a triangle, and the position of the relay determines which windings will be activated.
Typical mistakes and checking the result
After installing a new relay, many make the mistake of immediately turning on the refrigerator. This cannot be done. The posistor or thermal release requires time (usually 3 to 5 minutes) to cool down and restore its original state. If you turn on the unit earlier, the relay may not work, and the protection will turn off the motor again.
Turn on the refrigerator and listen. After a few seconds, you should hear a firm start-up click and the compressor will begin to operate with a uniform hum. If you hear only a single click and silence, or the motor hums and stalls, check again the orientation of the relay and the tightness of the contacts.
A common mistake is installing a relay of inappropriate power. Even if the device is physically suitable in size, its electrical characteristics (cut-off current) must correspond to the parameters of the compressor. Installing a relay with a high current may result in it not turning off the starting winding in time, causing overheating.
⚠️ Attention: Specifications of compressors and relays may vary depending on the model year. Always check the markings of the new relay with the data on the nameplate of the old device or in the passport of the refrigerator.
During the first hour of operation, periodically check the temperature of the body of the new relay. It may become slightly warm, but should not be so hot that it is impossible to touch. Excessive heating indicates poor contact or improper operation of the device.
Is it possible to install a relay of another brand, for example, from Indesit or Bosch?
Theoretically, this is possible if the electrical parameters (cut-off current, voltage) and the geometric dimensions of the seat match. However, it is better to use original spare parts Atlant or their direct analogues (for example, RT, RTK, RTP), since they are guaranteed to match the current characteristics of your compressor.
Why did the new relay burn out after a week?
Most often this happens due to problems with the compressor itself (turn-to-turn short circuit) or power surges in the network. It may also be due to incorrect installation (wrong orientation), due to which the relay does not open the starting circuit, and current continues to flow through the starting winding, causing overheating.
Does it need to be replaced when replacing the relay?
If your refrigerator model has a starting capacitor, it is recommended to check it. If it is swollen or has lost capacity, it should also be replaced. However, preventive replacement of a working capacitor is not necessary if there are no visible defects.
What to do if the compressor is hot to the touch?
Heating of the compressor to 70-90 degrees in the lower part is the norm for a running engine. However, if the upper dome or inlet pipes become hot, or if the temperature exceeds 100 degrees, this may indicate an overload, filling with the wrong freon, or a malfunction in the circulation system.