The situation when the refrigerator Posis stops cooling, but at the same time makes characteristic clicks or buzzes for only a few seconds before stopping, often indicates a failure of the engine starting mechanism. In most cases, the problem lies precisely in starting relay, which is responsible for starting the compressor windings and protecting them from overloads. If you are faced with similar symptoms, then self-diagnosis and replacement of this part can be an effective solution that allows you to save on calling a technician and extend the life of household appliances.
The process of removing the relay does not require complex professional equipment, but it does involve working with electrical components, therefore, it requires strict adherence to safety measures and attention to design details. Compressorsinstalled on refrigerators Pozisusually have a standard mounting pattern, but may differ in nuances depending on the engine model and year of manufacture of the unit. Before starting any work, it is necessary to completely de-energize the device by unplugging the plug from the socket to eliminate the risk of electric shock.
In this article we will analyze in detail the algorithm for removing the start-up relay, consider the typical causes of its breakdown and tell you how to correctly identify the part for replacement. Understanding the operating principle of this unit will help you not only replace it, but also understand whether the cause of the malfunction lies deeper, for example, in the heat dissipation system itself. A competent approach to repair will avoid repeated breakdowns and ensure correct operation of the refrigerator in the future. motor-compressor or heat removal system. A competent approach to repairs will avoid repeated breakdowns and ensure correct operation of the refrigerator in the future.
Diagnostics of a malfunction of the starting relay
Before proceeding with dismantling the part, you need to make sure that the problem really lies in the relay, and not in the lack of voltage in the network or thermostat failure. The main sign of a malfunction starting relay is a characteristic sound: the refrigerator hums for 5-10 seconds, then a loud click is heard and the motor stops. After some time, the cycle repeats. This indicates that the compressor is trying to start, but the starting winding does not receive the necessary impulse or the protection turns off the power due to overload.
Another method of primary diagnosis is visual inspection and “listening” to the part. If the relay has a plastic case, you can gently shake it near your ear. The presence of a rattling sound, like a broken coin inside, indicates destruction of the core or contacts inside posistor (in models with a solid-state start) or mechanical part. However, the final verdict can be made only after removing the component from the compressor casing.
⚠️ Attention: Do not try to diagnose the operation of the relay while the refrigerator is plugged in and under voltage. Touching live parts of a compressor or relay while the power is on is deadly.
You should also pay attention to external signs: blackening of the contacts, a burning smell or melting of the plastic of the relay case. If you notice traces of soot on the back wall of the refrigerator in the area of the motor, this may indicate that contacts the relays are burnt and begin to spark, which leads to local overheating. In such cases, replacement of the part is mandatory, since further operation can lead to combustion of the compressor windings.
Preparation of tools and work area
For successful removal of the relay from the refrigerator compressor Position you don’t need a whole arsenal of professional tools. A minimal set, which any home craftsman usually has, is sufficient. The main requirement for preparation is to ensure good lighting of the work area, since the back of the refrigerator is often darkened, and the parts are black or dark gray, which makes visual inspection of small elements difficult.
You will need the following tools for the work:
- 🔧 Pliers or pliers with narrow jaws - to remove the fixing brackets and clamps.
- 🔌 Screwdriver (cross or flat) - may be needed to remove the compressor protective casing.
- ✂️ Pliers or side cutters - for cutting wires if the terminals are stuck (used rarely).
- 🧤 Gloves —to protect hands from (oil) and sharp metal edges.
Before starting work, be sure to move the refrigerator away from the wall, ensuring free access to the back panel. If the model Pozis is equipped with a protective metal casing at the bottom, it must be dismantled. It is usually secured with latches or bolts. Removing the casing will provide access to compressor, the capacitor array and the starting fittings. Make sure that the floor under the refrigerator is covered with rags or cardboard, as technical oil or condensate may drip from the compressor.
☑️ Preparation for repair
Removing the protective casing and access to the compressor
On most refrigerator models Position (Ripple, World, Tent) compressor is the lower rear part of the unit and is often closed with a metal or plastic box. This casing serves as protection against dust, moisture and accidental mechanical damage, and also directs air flow to cool the engine. To remove it, carefully inspect the perimeter: screws, self-tapping screws or plastic latches can serve as fastening elements.
If the casing is metal and secured with screws, use an appropriate screwdriver. In older models, the screws may be coated with a layer of rust or dirt, so before unscrewing them, you can treat them with a penetrating lubricant (such as WD-40) to prevent the heads from being stripped. Plastic panels are usually held in place by clips that require gentle pressing with a flat object. Act without excessive force so as not to break the plastic, which is fragile over time. plastic.
After removing the protection, you will see a view of the compressor - a black metal “tank” with outgoing copper tubes. At the bottom of the compressor, where the electrical wires come out, is the part you are looking for. Please note that in some configurations, access to the relay may be partially limited by the capacitor or tubing refrigerant. In such cases, you may need to carefully bend the tube by hand (only if it is not hot or under pressure) or temporarily remove the clamps holding the wires.
It is important to remember or photograph the original position of all elements before removing them. This will help avoid errors during reassembly. This is especially true for the position of the terminals and the direction of installation of the relay itself relative to the compressor rod.
⚠️ Attention: It is strictly forbidden to bend the copper tubes of the cooling system at an acute angle. Deformation of the tubes can lead to disruption of freon circulation or depressurization of the circuit, which will require expensive refilling of the refrigerator.
Algorithm for dismantling the start relay
The process of removing the relay itself is a key stage of repair. The starting device on refrigerator compressors Position (motors Danfoss, Secop or domestic SKNare often used) is attached directly to the terminals of the compressor. It is a box with connectors, which includes three contacts from the motor. Fixation is carried out either due to a tight fit on the contacts and the springy properties of the plastic, or using a metal bracket-clamp.
Let's consider a step-by-step algorithm of actions:
- Disconnecting the wiring: First of all, you need to disconnect the wires, going from the relay to the capacitor and the power cord. They are held on by terminals. Clamp the terminal with pliers (not the wire itself!) and pull gently. If the terminals are oxidized and cannot be removed, you can slightly warm them with a hairdryer, but not with an open fire.
- Removing the fixing bracket: Carefully inspect the relay base. If the metal U-shaped bracket covering the relay housing and compressor terminals is visible, it must be removed. Pry the bracket with a screwdriver or pliers and pull it down or to the side, depending on the design.
- Removing the relay: If there is no bracket, the relay is simply put on the contacts. Take the relay body with both hands (or with pliers by the special ears, if any) and gently pull it down with rocking movements from side to side. Do not apply excessive force up or to the side so as not to break the ceramic insulators of the compressor terminals.
In some cases, the relay may “stick” to the terminals due to prolonged heating and oxidation. If you cannot remove it by hand, you can use two flat-head screwdrivers, prying the relay housing from two opposite sides at the same time and pressing down evenly. The main thing is to maintain the axis of movement strictly vertically downwards, repeating the angle of inclination of the compressor leads.
| Type of fastening | Characteristic features | Removal tool | Risks during removal |
|---|---|---|---|
| Spring bracket | Metal arc on top | Pliers, screwdriver | Loss of bracket, hand injury |
| Tight fit | No visible latches | Only hands | Broken compressor leads |
| Screw connection | Screws on the case (rarely) | Screwdriver | Thread breakage |
After the relay is removed, inspect the seat on the compressor. There should be no soot, oxides or moisture. If the compressor leads are blackened, they must be carefully cleaned with fine sandpaper or a file to a shine to ensure a good electrical contact with the new part.
Checking the removed relay and selecting a replacement
After removing the relay from the refrigerator Posis it is necessary to troubleshoot it in order to understand whether it can be repaired or requires replacement. Visually inspect the housing: the presence of cracks, traces of melting or burning indicates that the part was operating in emergency mode. If the case is intact, you can try to open it (if it is not cast) and inspect the internal contacts. Burnt contacts can be cleaned, but this is a temporary measure.
The most reliable way to check is a continuity test with a multimeter. Depending on the type of relay (inductive or posistor), the test logic will be different:
- 🔋 Induction relay: The coil and contacts are checked. In the normal position the contacts are open. When current is applied (which is difficult to check without a stand), they should close. They often check “on weight”: if you shake it and a ringing sound is heard, the core is loose, the relay is faulty.
- ⚡ Posistor relay: Has a solid-state element (posistor). When cold, it should have low resistance (tens of ohms). If the multimeter shows an open circuit or a resistance close to infinity, the posistor has burned out.
When choosing a replacement, it is critical to select a relay with identical characteristics. There is always a marking on the body of the part. For refrigerators Pozis relays of the RT series (for example, RT-12, RT-21) or P3are often used. The number in the marking usually indicates the maximum permissible current of the compressor. Installing a relay with a lower current will lead to constant shutdowns, and with a higher current, it will burn out the motor windings during startup.
⚠️ Attention: Never install a relay designed for compressors of a different type (for example, for high-pressure instead of low-pressure). This will lead to instant failure of the new relay and a possible wedge of the compressor.
Frequent errors during removal and installation
The process of replacing a relay seems simple, but beginners often make mistakes that can negate all efforts or lead to a new breakdown. One of the most common mistakes is the use of physical force when removing a “stuck” relay. A sharp jerk can break the glass or ceramic terminals of the compressor, which is a fatal breakdown for the entire unit. Compressor in this case, you will have to replace the whole thing, which is not economically feasible.
Another mistake is ignoring cleaning the contacts. Installing a new relay on oxidized or burnt motor leads will result in the new part also burning out in a short time. Poor contact causes heat, which destroys plastic and metal. Always take the time to prepare the mounting location.
It is also worth mentioning the installation orientation error. The relay body often has an arrow or inscription UP / TOP. The relay must be installed strictly in the position in which it initially worked (usually the arrow points up). Violation of this rule in induction relays will result in the movable core not being able to move correctly under the influence of gravity and the electromagnetic field, and starting the compressor will become impossible.
FAQ: Frequently Asked Questions
Is it possible to start a refrigerator without a relay temporarily?
Theoretically start A compressor without a starting relay is possible by applying voltage directly to the starting winding through a button only at the time of start, but this requires a qualified electrician. Operate the refrigerator without a working relay strictly prohibited. This will lead to overheating and burning of the compressor starting winding within a few minutes or even seconds.
Why does the new relay click, but the refrigerator does not turn on?
If after replacing the relay you hear clicks, but the compressor does not start (or hums and switches off), there may be several reasons: the compressor itself is faulty (interturn short circuit or wedge), the relay is incorrectly selected (wrong current), or the problem is in the thermostat/starting capacitor. It is also worth checking the voltage in the network.
Where can you find the relay markings on the Pozis refrigerator?
The markings are applied directly to the body of the plastic or black ebonite relay box. To see it, the relay does not have to be completely removed; just pull back the compressor protective casing. Look for inscriptions like RT-12, 17.123, P3 and numbers indicating current (for example, 1.1, 1.4, 2.2).
How long does the starting relay last?
The average service life of the starting relay is 5-10 years, but it greatly depends on the stability of the voltage in the network, the number of cycles turning on/off the refrigerator and the room temperature. Frequent power surges significantly reduce the service life of the part.