Sudden stoppage of the compressor or its characteristic knocking often indicates problems in the electrical engine starting circuit. In refrigerators Atlant, which are widespread in the post-Soviet space, one of the most common causes of breakdown is the failure of the start relay. This small but critical component is responsible for supplying voltage to the motor windings at the moment of start. If it does not work, the refrigerator stops freezing, and food begins to deteriorate.
Before calling a technician or buying a new unit, it makes sense to conduct independent diagnostics. A start relay is an electromechanical device that can be tested using a simple multimeter without in-depth knowledge of electronics. In this article, we will analyze in detail the relay design, signs of its malfunction and the algorithm for checking and replacing it. Safety When working with electrical appliances comes first, so do not ignore the rules for turning off the power.
Symptoms can vary from complete silence of the unit to cyclic clicks. Understanding exactly how your Atlant refrigeratorbehaves will help you more accurately determine the diagnosis. Sometimes the problem lies in the relay itself, and sometimes the compressor winding is to blame. Careful inspection and testing of contacts will help to distinguish between these conditions. Let's look at all the stages of diagnostics in detail.
Design and principle of operation of the starting relay
The starting relay in refrigerators Atlant performs the function of an automatic switch. When the refrigerator is turned on, voltage is supplied to the operating winding of the motor and at the same time to the relay coil. The current passing through the coil creates a magnetic field that draws in the core and closes the contacts of the starting winding. This provides the necessary impulse to spin up the compressor rotor.
As soon as the engine reaches the required speed, the current in the circuit drops, the magnetic field weakens, and the spring opens the contacts of the starting winding. Then the motor operates only on the working winding. Models Atlant often use induction-type relays (RT, R-1, R-2 series) or posistor (for more modern inverter or two-compressor models). Induction relays have moving contacts, which can burn or stick over time.
It is important to understand that inside the relay case there is not only an electromagnet, but also a thermal protection relay. It reacts to overcurrent or overheating of the compressor. If the motor jams or the current exceeds the norm, the bimetallic plate heats up and opens the circuit, preventing the windings from burning out. Thermal protection This is the second level of safety for your refrigerator.
⚠️ Attention: Inside the start relay housing there are high-voltage contacts. Never touch live parts while the device is connected to the mains. Carry out all manipulations to remove and check the relay only with the refrigerator disconnected from the power supply.
Structurally, the relay is mounted directly on the side rod of the compressor. It is protected by a plastic or metal casing. In older models Atlant there are relays with an open contact system, in new ones they are completely sealed. The principle of operation remains similar, but diagnostic methods may differ slightly depending on the type of contacts.
What is the difference between induction and posistor relays?
Induction relays have a movable core and contacts that physically open. PTC relays operate on the basis of a ceramic element that changes resistance when heated, and have no moving mechanical parts in the trigger circuit. PTC resistors are considered more reliable, but are sensitive to shock.
Typical signs of a relay malfunction
You can determine that the problem lies in the starting relay by the characteristic sounds and behavior of the compressor. Most often, refrigerator owners Atlant face a situation where the motor tries to start, but immediately stalls. This is accompanied by a loud click, after which there is silence for several minutes until the thermal protection cools down.
Another common symptom is a characteristic crackling or buzzing sound without starting. The compressor hums, trying to get off the ground, but the rotor does not turn. If you do not turn off the power at this point, there is a risk of burning the motor winding. Also, a malfunction may be indicated by the absence of any sounds of the refrigerator operating while the light inside the chamber is on.
Visual inspection can also provide important clues. If you remove the protective cover and see melted plastic, blackened contacts, or smell a burning smell, then the relay definitely requires replacement. Sometimes the relay housing cracks due to overheating or mechanical stress.
- 🔊 The compressor clicks and immediately turns off - a sign that the thermal relay has tripped due to the impossibility of starting.
- 🔇 Complete lack of response from the motor when plugged in, although the light in the chamber is on.
- 🔥 The smell of burnt insulation or visible traces of soot on the relay body.
- 🔄 The refrigerator turns on and off every 2-3 minutes (cyclic operation).
It is worth noting that similar symptoms may appear during an interturn short circuit in the compressor windings or jamming of the piston group. Therefore, checking the relay is only the first stage of diagnosis. If the relay is working properly, but the motor does not start, the problem may be deeper. Diagnostics must be complex.
Removing the start relay from the compressor
To start working, you need to gain access to the compressor. In refrigerators Atlant it is usually located in the lower rear part of the unit. Remove the back metal panel by unscrewing the mounting screws. You will have a view of the motor-compressor, condenser grille and starting unit.
Make sure that the refrigerator was unplugged at least 15-20 minutes ago. This is necessary so that the capacitors discharge and the compressor cools down. Carefully remove the plastic protective cover that covers the relay connection point. It can be held on by latches or screws.
The relay itself is mounted on three pins coming out of the compressor housing. Depending on the model Atlant, it can be additionally fixed with a metal bracket or plastic clips. If there is a staple, carefully bend it back with pliers. Do not use excessive force to avoid damaging the tubes or wires.
⚠️ Attention: When removing the relay, proceed carefully. The compressor pins are fragile and can break off with a sudden jerk. If the relay is stuck or tight, rock it slightly from side to side, but do not aggressively pull upward.
Disconnect the wires going to the relay. They can be secured to the terminal block or simply slipped onto the contacts. Before disconnecting, it is recommended to take a photo of the connection diagram with your phone so as not to mix up the wires during assembly. The color marking of wires in different models Atlant may differ.
☑️ Dismantling algorithm
External inspection and primary diagnostics
After removing the relay from its seat, perform a thorough visual inspection. Shake the relay near your ear: if you hear a rattling sound inside, like a loose nut, it means the contacts have broken or the core has come off. A working relay should not make sounds when shaking.
Inspect the contact group. There should be no black deposits, spark pits or oxides on the copper contacts. If the contacts are blackened, this indicates poor contact and overheating. In some cases (for experienced craftsmen) it is possible to clean the contacts, but at home it is easier and more reliable to make replacement node.
Check the integrity of the plastic case. Cracks may indicate overheating or mechanical shock. Also inspect the wires for melted insulation. If you see traces of soot inside the relay housing, you absolutely cannot use it any further - it is a fire hazard.
For models with a posistor starter, the visual defect may not be visible. A posistor is a ceramic tablet that changes resistance when heated. If there are chips or cracks on it, the element is faulty. However, most often the posistors look intact even in a non-working state, so an instrumental check is required.
Checking the relay with a multimeter
The most accurate diagnostic method is to test the contacts using a multimeter (tester). Switch the device to resistance measurement mode (Ohm) or continuity mode. First check the integrity of the inductor. Connect the probes to the corresponding relay contacts. The resistance should be within normal limits (usually from 3 to 30 Ohms, depending on the model).
If the device shows one (infinity), then there is a break in the coil, and the relay will not be able to create a magnetic field to start. If it shows zero, there is a short circuit in the turns. In both cases replacement is required. Also check the thermal relay: its contacts should ring when cold (resistance is close to zero).
To check the operation of the mechanism (only for induction relays in a vertical position): apply voltage to the coil (being careful!) or carefully turn the relay over. In the operating position, the contacts of the starting winding must close. However, it is safer to check the resistance between the contacts in different positions of the core, if the design allows this to be done without applying current.
Below is a table of typical values and states for diagnostics:
| Check element | Normal state | Symptom malfunction | Action |
|---|---|---|---|
| Inductor | Resistance 3-30 Ohm | Open (∞) or short circuit (0 Ohm) | Replacement relay |
| Thermal relay contacts | Closed (0 Ohm) | Open in cold state | Replacing the thermal relay |
| Posistor | Resistance 10-50 Ohm (cold) | Short circuit or break | Replacing the posistor |
| Mechanical part | No backlash and noise | Knocking, rattling, jamming | Replacing the relay |
Dynamic processes (opening of contacts when revving up) are difficult to check at home. Therefore, if visually and by resistance the relay seems to be working, but the refrigerator does not start, the method of eliminating or replacing a known good relay is often used.
Replacement and operation check compressor
If the diagnostics showed a faulty relay, it must be replaced. Installation of a new element is carried out in the reverse order of removal. Push the relay onto the compressor pins as far as it will go. Make sure that it sits tightly and vertically (for induction relays this is critical, since the core must move freely under the influence of gravity).
Connect the wires according to the photograph or diagram you took earlier. Attach the fixing bracket. Install the protective cover and rear panel of the refrigerator. Only after complete assembly can you connect the device to the network. When you turn it on for the first time, listen carefully: you should hear a click of the relay, a hum of the compressor, and after 10-20 seconds a second click of the starting winding turning off.
If the compressor starts and runs smoothly, without buzzing or vibration, then the problem is solved. Check the cooling of the chambers after 30-40 minutes of operation. If the situation repeats (clicking and silence), perhaps the problem is not in the relay, but in the compressor itself (jamming or breakdown of the windings) or in the wiring.
⚠️ Attention: Technical characteristics of refrigerators Atlant may vary depending on the year of manufacture and model. If you are not confident in your abilities or the refrigerator does not work after replacing the relay, contact an authorized service center for professional diagnostics.
Sometimes, to start an old compressor, you need to install a relay with slightly different characteristics (for example, with a large starting torque), but this is a temporary solution. Operating a faulty compressor with an unsuitable relay can lead to its complete failure. Resource The motor capacity in this case is sharply reduced.
Is it possible to repair an old relay?
Theoretically, The contacts can be cleaned with fine sandpaper, and the moving parts can be lubricated with graphite lubricant. However, the factory seal will be broken, which will lead to oxidation of the contacts in the future. For reliable operation of the Atlant refrigerator, only complete replacement of the unit is recommended.
Frequently asked questions (FAQ)
Where is the relay marking on the Atlant refrigerator?
The marking is usually applied to the side or top edge of the plastic relay case. Also, information about the type of relay (for example, R-1, RTK-1, 100N001) can be indicated in the technical documentation of the refrigerator or on a sticker inside the chamber.
Why does a new starting relay burn out?
A common reason is unstable voltage in the network or problems with the compressor itself (hard start, interturn short circuit). If the relay burns out repeatedly, you need to check the voltage in the socket and the current consumption of the compressor.
Is it possible to start a refrigerator without a starting relay?
Theoretically, you can apply voltage to the starting winding manually for 1-2 seconds, but this is extremely dangerous and requires skills. Without a relay, the compressor will not be able to work for a long time and will burn out. Operation without a relay is prohibited.
How much does a starting relay cost for Atlanta?
The price depends on the type of relay and manufacturer. Conventional induction relays are inexpensive, posistor relays can be more expensive. On average, the cost of the part is affordable for self-repair.
Does the position of the refrigerator affect the operation of the relay?
Yes, especially for induction relays. The refrigerator must be strictly level. Tilt can disrupt the operation of the moving core inside the relay, which will lead to failure to start or sticking contacts.