A sudden stop in the operation of a refrigeration unit often takes you by surprise, especially when there are perishable products in the chamber. If you notice that the motor-compressor either does not start at all, or makes short humming sounds and immediately turns off, the problem most likely lies in the start-protection relay. This small but critical element is responsible for supplying voltage to the motor windings and protecting against overloads.
Equipment owners Pozis face similar situations quite often, since the life of the part is limited, and voltage drops in the network can accelerate its failure. Replacing a relay yourself is a procedure that is accessible even to a beginner, if you strictly follow safety precautions and the sequence of actions. In this article, we will look at how to correctly diagnose a breakdown, dismantle the old element and install a new one, avoiding common mistakes.
Before starting disassembly, you need to make sure that the refrigerator is disconnected from the power supply. Working with live electrical equipment is strictly prohibited and may result in serious electrical shock. In addition, for the job you will need a minimum set of tools: flat-head and Phillips screwdrivers, a multimeter (preferably) and pliers.
Diagnostics of a relay failure
The first step should always be an accurate diagnosis, since the symptoms of a relay failure may be similar to a malfunction of the compressor or thermostat itself. If, when you plug in the refrigerator, you hear a quiet click, followed by a motor hum for 3-5 seconds, and then a loud shut-off click, this is a classic sign of operation. The relay tries to start the engine, but due to an open or short circuit in the starting winding, the current increases sharply, and the protection opens the circuit. thermal protection. The relay tries to start the engine, but due to a break or short circuit in the starting winding, the current increases sharply, and the protection opens the circuit.
Visual inspection can also provide a lot of information. After removing the casing, inspect the relay body for melting, blackening or cracks. If you hear a ringing sound inside when you shake it (like breaking glass), it means that the contacts or mechanical parts are damaged. However, external integrity does not guarantee serviceability, so the most reliable method is checking with a multimeter.
- 🔍 Visually inspect the contacts for carbon deposits or oxidation, which may prevent the flow of current.
- 🔊 Listen for characteristic clicks: a series of rapid clicks indicates an attempt to start and activation of the protection.
- 📏 Ring the contacts with a tester in resistance measurement mode: a working relay should “ring” in certain combinations.
⚠️ Attention: If the compressor hums but does not start, and the motor housing gets very hot, do not try to turn on the refrigerator repeatedly. This can lead to an interturn short circuit of the windings and complete failure of the expensive unit.
Often owners confuse a relay malfunction with a thermostat failure. To exclude this, you can close the contacts of the thermostat (if you are confident in your actions), but in the case of a relay Pozis it’s easier to immediately remove it and check it. If, after replacing the part with a known good one, the refrigerator started working, then the diagnosis was correct.
Preparing tools and ensuring safety
High-quality repairs are impossible without proper preparation of the workplace. To replace the relay on the refrigerator Pozis you do not need a complex professional tool, but having everything you need on hand will speed up the process and reduce the risk of damage to the plastic elements of the case.
You will need: a Phillips screwdriver (usually PH2 size) to remove the protective casing, a flat screwdriver to carefully disconnect the terminals, pliers (pliers) for fixing wires and, preferably, a multimeter for the final check. It is also recommended to prepare a clean rag and possibly contact spray to treat the connections if they are oxidized.
☑️ Preparing to replace the relay
Pay special attention to lighting. The back wall of the refrigerator is a dark place, and poor light can cause you to accidentally damage copper pipes or connect wires incorrectly. Make sure the floor is dry and your hands are not wet.
⚠️ Attention: Before starting any work, be sure to unplug the power cord from the outlet. Even if the refrigerator is not working, residual voltage may remain in the circuit, and accidental switching on during manipulation of the contacts is dangerous.
Access to the compressor and removal of the protective casing
Refrigerators Pozis, like most models of the classic layout, have a compressor located in the lower rear part of the case. To access it, you must remove the protective metal or plastic casing. Depending on the year of manufacture of the model, the method of fastening may differ.
In older models, the casing is often secured with bolts around the perimeter or with special latches. Carefully remove all visible screws using a suitable screwdriver. Do not use excessive force: if the element does not budge, check whether another bolt is hidden under a sticker or rubber plug. Modern models Pozis often use a system of latches that open by lightly pressing or sliding the cover down.
After removing the casing, you will have a view of the motor-compressor, the condenser grille (if it is not built into the wall) and the same start-up device that is attached directly to the compressor terminals. Be careful not to sharply pull the wires or touch the copper tubes coming from the compressor - they are thin and easily deformed.
Inspect the area around the compressor for traces of oil. If you see oily spots on the floor under the refrigerator or on the casing itself, this may indicate depressurization of the system, which requires not replacing the relay, but calling a technician to look for a freon leak.
Removing the old start relay
The process of removing the relay itself is quite simple, but requires care. The starting device on refrigerators Pozis usually fits directly onto the three contact pins coming out of the compressor housing. It is secured either by a tight fit or by a metal retaining bracket.
If the relay is held in place by a bracket, carefully bend it back with pliers or pry it off with a flat-head screwdriver. Don't pull the wires! First you need to remove the plastic relay box itself from the compressor contacts. Take the relay with your hand (or with pliers if your fingers are uncomfortable, but carefully so as not to crumble the old plastic) and pull it down with rocking movements from side to side.
After the relay is removed from the compressor contacts, you need to disconnect the wires coming from the network. There are usually two or three of them, and they are connected through a terminal block or directly into the relay housing. Remember or take a photo of which wire is connected where. Color coding may be standard, but it is better to double-check visually.
- 🛠️ Carefully bend the metal fasteners, if present, using a flat-head screwdriver.
- 📸 Take a photo of connecting the wires before disconnecting them, so as not to confuse the polarity during assembly.
- 🔌 Disconnect the wires by holding the plastic part of the terminal, and not the wire itself, so as not to break the wires.
Sometimes the wires can be “sticky” or oxidized. In this case, you can move the terminal slightly, but do not use brute force. If the terminal is put on tightly, use pliers to remove it, having first de-energized the system.
Marking and selecting a new relay
The selection of the correct analogue is a critical point. Starting relays for refrigerators Pozis (as well as for other brands like Atlant or Indesit) are not universal "for everyone". They are selected strictly according to the power and type of compressor.
There is always a marking on the body of the old relay. Look for designations starting with RT (for example, RTK-1, RTK-1.3, RT-21, RT-23, RT-24). The numbers indicate the rated current or power for which the device is designed. Installing a relay with inappropriate parameters will either prevent the refrigerator from starting or burn out the compressor windings.
What do the numbers in the marking mean? relay?
The numbers in the marking (for example, RTK-1.3) indicate the rated current of the protection. Relay RTK-1 is suitable for low-power compressors, RTK-1.3 for medium-sized ones, and RT-23/24 for more powerful units. Using a relay with a lower current will lead to a permanent shutdown, while using a higher current will result in a lack of protection.
The table below shows the types of relays used in refrigerators Pozisand their compatibility:
| Relay marking | Type compressor | Features | Compatibility |
|---|---|---|---|
| RTK-1 | Low power | Vertical mounting | Old models Pozis, Biryusa |
| RTK-1.3 | Medium power | Vertical mount | Most Pozis models |
| RT-21 | Medium power | Horizontal mount | Analogue for RTK-1.3 |
| RT-23 / RT-24 | Increased power | Horizontal/Vertical | Two-compressor models |
If you do not find exactly the same relay as was installed, you can use a complete analogue from other manufacturers (for example, Atlant), the main thing is the coincidence of the current characteristics and the type of mounting (vertical or horizontal). Pay attention to the location of the contacts: they must coincide with the terminals on the compressor.
Installation and connection of a new relay
The process of installing a new start-protective device is performed in the reverse order. First, connect the power wires to the appropriate terminals on the new relay. Make sure the connection is tight and secure. If the terminals are loose, they can be carefully tightened with pliers.
Then put the relay on the compressor pins. It should fit tightly, without play. The orientation of the relay must strictly correspond to the markings on the housing (usually indicated by "UP" or an upward arrow). Incorrect orientation (upside down) will result in the mechanism not working and the compressor burning out.
After installing the relay, return the protective casing to its place and secure it him. Now you can turn on the refrigerator. Pay attention to the first start: the motor should start in a few seconds (the delay is needed to equalize the pressure in the system) and run smoothly, without buzzing or vibration.
If the refrigerator starts and gets cold, it means the repair was successful. Let the unit operate for several hours without loading food to make sure that the operation is stable and the temperature is set correctly.
Frequent errors and troubleshooting
Even after following all the instructions, beginners can make mistakes that will lead to repeated breakdowns. One of the most common is ignoring the condition of the capacitor. The starting capacitor (if your model has one, usually the black cylindrical element next to the relay) also tends to fail. If you replace the relay, but leave a broken capacitor, the new relay will also quickly burn out.
Another error is poor contact in the terminals. If you do not tighten the terminal or there is oxidized residue left in the connector, heating and sparking will begin to occur at the contact point. This can lead to melting of the relay plastic and even fire. Always clean the contacts and check the tightness of the wires.
- 🔥 Error: Installing a relay of inappropriate power (too weak). Result: constant clicks and disconnections.
- 🔌 Error: Loose wire connection. Result: sparking, heating, risk of fire.
- 🔄 Error: Ignoring capacitor check. Result: repeated failure of the new relay.
⚠️ Attention: If after replacing the relay the compressor hums but does not start, and you can hear a burning smell, immediately turn off the refrigerator. Most likely, the compressor itself is jammed (mechanical failure), and no amount of electrical replacement will help. Professional repair or replacement of the motor is required.
It is also worth mentioning the importance of cleanliness in the compressor area. Dust wrapped around the windings or clogged in the relay can cause overheating. Regularly (once a year or two) vacuum the back wall of the refrigerator.
FAQ: Frequently asked questions
Is it possible to start a refrigerator without a relay?
Theoretically, you can start the engine by applying voltage directly to the working and starting windings, but do this in a domestic environment absolutely not recommended. This requires precise knowledge of the circuit, the presence of a starting capacitor and the ability to control the timing of the pulse. In addition, without thermal protection, the compressor will remain defenseless against overheating and will quickly burn out. This is an emergency measure for diagnostics, but not for operation.
How much does a relay cost for a Pozis refrigerator?
The cost of a start-up relay varies depending on the model and manufacturer. Domestic analogues (for example, RTK) are cheaper, usually in the range from 500 to 1000 rubles. Imported or specialized relays can cost from 1000 to 2000 rubles. This is much cheaper than calling a technician, taking into account the cost of the work.
Why does a new relay burn out immediately after installation?
If a new relay burns out instantly or after a short time, there may be several reasons: 1) The compressor itself is faulty (turn-to-turn short circuit of the windings), which causes excessive current consumption. 2) The starting capacitor is broken. 3) The relay power is incorrectly selected (the rating is too low). 4) Poor contact in the power circuit.
Is it possible to use a relay from another brand, for example, Atlant?
Yes, you can if the technical specifications match. Refrigerators Pozis are often equipped with compressors and relays that are interchangeable with components Atlant, Indesit or Stinol. The main thing is to pay attention to the markings (RTK, RT) and the type of fastening (vertical/horizontal). The numbers in the marking should be as close as possible to the original.