Sudden cessation of compressor operation or its characteristic a humming sound without starting often indicates a failure of the start-up relay. This small part plays a critical role in the system refrigeration unit, being responsible for supplying voltage to the motor windings. Owners of household appliances Atlant often face the need to replace this element, since its resource is limited by on and off cycles.
Independent replacement allows you to save on calling a technician, but requires strict adherence to safety precautions and understanding of the circuit connections. Incorrect installation can lead to short circuit or complete combustion of the compressor. It is important to understand that a relay is not just a switch, but a complex mechanism with thermal and starting units.
Before you start disassembling, you need to make sure that the problem lies in this component. Often the symptoms of a relay malfunction are confused with a breakdown of the motor or thermostat itself. Competent diagnostics will save time and money, allowing you to accurately determine the cause of equipment failure.
The design and principle of operation of the start-up protection relay
The start-up protection relay in refrigerators Atlant represents is a combined device that combines starting and thermal protection. Inside the case there are contacts that open when the bimetallic plate is heated, and a starting coil. The principle of operation is based on a sharp jump in current at the moment the engine starts, which causes a short circuit in the starting winding.
Thermal protection is triggered if the current in the circuit exceeds permissible limits or if the compressor overheats. The bimetallic plate bends and opens the circuit, preventing the windings from burning out. After cooling, the contacts close again, trying to start the engine. If the malfunction is not eliminated, the cycle is repeated, producing characteristic clicks.
⚠️ Attention: Operating a refrigerator with a constantly clicking relay leads to rapid overheating and destruction of the insulation of the compressor windings. At the first signs of unstable operation, you must disconnect the device from the network.
The design of the relay may vary depending on the model of the refrigerator and the type of compressor used. Modern models often use solid-state relays, which have no moving mechanical parts. However, most household refrigerators Atlant still use classic electromechanical devices that require periodic replacement.
What is the difference between relays for different compressors?
Relays for single-phase compressors have one starting winding, while for The two-phase connection diagram is more complicated. It is important to take into account the markings and number of contacts when purchasing a replacement.
Diagnostics of faults before replacement
Before disassembling the unit, an initial check should be carried out. If the refrigerator does not turn on, but the light inside is on, this is the first sign of problems with the starting circuit. You need to listen: if you hear a motor hum that lasts several seconds, followed by a click and silence, then most likely the piston group is not working or the piston group is jammed. starting winding or the piston group is jammed.
Visual inspection of the relay can also provide a lot of information. Remove the cover and inspect the part for blackening, melted plastic, or a burning smell. Often you will notice charred contacts inside the case that do not conduct current properly. In some cases, the problem lies in the oxidation of the terminals.
For accurate diagnostics, use a multimeter in continuity mode. The resistance between the contacts must correspond to the technical specifications specified in the documentation. Lack of conductivity or, conversely, a short circuit indicates the need to replace the part. Do not ignore checking the thermal relay, as it often fails simultaneously with the starting one.
Preparation of tools and safety measures
Working with electrical equipment requires strict adherence to electrical safety rules. The first and most important step is to completely disconnect the refrigerator from the electrical network. It is not enough to simply turn off the button; you must unplug the cord from the outlet to eliminate the risk of electric shock if you accidentally touch live parts.
To carry out the work, you will need a minimum set of tools. The main attention should be paid to the insulation of the handles, since even when the device is turned off, a residual charge may remain in the capacitors. It is also recommended to prepare a clean rag to remove dust and dirt from the compressor contacts.
- 🔧 Screwdrivers (flat and Phillips) for removing the back panel and clamps.
- 🔌 Multimeter or tester to check the continuity of circuits.
- 🧤 Dielectric gloves for protection hands.
- 🔦 Flashlight for illuminating the working area in the compressor niche.
Ensure good lighting of the workplace. The compressor area is often obscured by the refrigerator body, and poor visibility can lead to wiring errors. If you are working in a garage or basement, use a portable lamp.
Removing the old relay and preparing for installation
The process of removing the old relay begins with dismantling the protective cover at the back of the refrigerator. It is secured with latches or screws. Be careful, the plastic becomes brittle over time and may crack if handled carelessly. After removing the cover, access to the compressor and the relay attached to it will open.
The relay is usually fixed on the three terminals of the compressor and is additionally secured with a bracket or frame. First you need to remove the retaining frame, which can be pressed with spring clips. Then carefully, rocking from side to side, remove the relay housing from the motor terminals. Sudden movements can damage the ceramic terminal insulators.
Disconnect the wires from the contact group. Remember or write down which wire went to which terminal. Color coding may be standard, but it is better to double check visually. Often the wires have terminals that are simply removed by hand or using pliers with thin jaws.
☑️ Removal procedure
Connection diagram and installation of the new relay
Installation of the new relay is done in the reverse order dismantling. The key is the correct orientation of the part relative to the compressor. The relay body usually has an arrow or inscription TOP, UPindicating the top position. Incorrect installation (upside down) will lead to incorrect operation of the thermal protection and rapid failure of the new part.
The connection of the wires must be carried out strictly according to the diagram. Typically, the contacts are numbered or have letters. For single-phase refrigerator compressors Atlant the following pinout is typical:
| Contact designation | Function | Wire color (standard) | Position on relay |
|---|---|---|---|
| L (Line) | Phase input | Red / Brown | Upper left |
| S (Start) | Start winding | Black / White | Upper right |
| R (Run) | Working winding | Green / Blue | Bottom center |
| Ground | Grounding | Yellow-green | On the body |
After putting the relay on the compressor terminals and connecting the wires, secure the part with a fixing bracket. Make sure that the wires do not touch hot parts of the compressor and are not pinched. Put on the protective cover and secure it. Only after complete assembly can you plug in the refrigerator.
⚠️ Attention: It is strictly forbidden to turn on the refrigerator without a protective cover and grounding installed. This creates a risk of electric shock and moisture on the contacts.
Checking operation and possible errors
After turning on the refrigerator, listen to the operation of the unit. The engine should start smoothly, without buzzing or clicking. After 10-15 minutes of operation, check the temperature of the condenser (grid at the back) - it should begin to rise evenly. This indicates normal refrigerant circulation.
If the compressor hums but does not start, turn off the device immediately. There may be an error in connecting the wires to the contacts starting winding. The cause may also be a defect in the new relay or a compressor malfunction that could not be identified at the diagnostic stage. In this case, a re-check of the circuit is required.
Sometimes after replacing the relay, the refrigerator works normally, but after a while it turns off again. This may indicate that the cause of the breakdown lay not only in the relay, but also in contamination of the contacts of the thermostat or a malfunction of the starting capacitor (if your model has one). An integrated approach to repair guarantees the durability of the result.
- ✅ The compressor started on the first try without any extraneous sounds.
- ✅ The rear grill heats up evenly over the entire area.
- ✅ Cold appears in the refrigerator compartment after an hour.
- ✅ There is no smell of burning or scorched insulation.
You should not expect instant freezing of food. The refrigerator needs time (from 2 to 5 hours) to reach operating mode and stabilize the temperature. During the first hours of operation, it is better not to load the chamber with products, so as not to create unnecessary load on the compressor.
What to do if the new relay immediately burns out?
This may indicate an interturn short circuit in the compressor windings or jamming of the piston group. In this case, replacing the relay is pointless; serious repairs or replacement of the compressor are required.
Frequently asked questions (FAQ)
Is it possible to install a relay from another refrigerator model on the Atlant?
Technically possible if the mounting dimensions, number of contacts and electrical characteristics (starting current, type) match compressor). However, the use of original spare parts or complete analogues guarantees stable operation. Experimenting with unsuitable relays can lead to compressor failure.
Why does a refrigerator relay often burn out?
Frequent burnouts can be caused by power surges, frequent power outages, a thermostat malfunction (too frequent cycles) or problems with the compressor itself (difficult starting). It is recommended to install a voltage stabilizer.
How long does it take to replace a relay?
For an experienced technician, the process takes 15-20 minutes. When replacing yourself, taking into account diagnostics and preparation of tools, you should allow about 40-60 minutes. The main thing is to take your time and follow safety precautions.
Do you need to defrost the refrigerator before replacing the relay?
Full defrosting is not necessary, since access to the relay is from the rear. However, if you plan to move the refrigerator and there is a risk of damaging the ice crust in the freezer when tilted, it is better to defrost the unit in advance.