A sudden failure of refrigeration equipment often takes you by surprise, but in many cases the cause of the breakdown is precisely starting relaywhich can be replaced independently. This small part is responsible for starting the compressor engine, and its failure leads to the fact that the unit either stops turning on or operates with a characteristic hum without cooling. Understanding how to correctly remove the relayis the first and most important step in diagnosing a malfunction.
Before taking active steps, you need to realize that you will be working with electrical equipment connected to the 220 network volts Any manipulations inside the housing, especially near the compressor, require strict adherence to safety precautions and complete disconnection of the device from the power supply. Ignoring this rule may result in serious electric shock or damage to electronics.
In this article we will analyze in detail the algorithm for removing relays from compressors of various types, including common models Atlant, Indesit and Stinol. You will learn what tools are needed for the job, how to distinguish a serviceable part from a burnt one, and what to pay special attention to when removing components so as not to damage the fragile system tubes.
Locating and preparing tools
The first stage of any repair is localization of the problem node. The start-up relay is always located directly on the compressor housing, which is usually located at the lower rear of the refrigerator. To access it, you will need to remove the back metal panel, secured with screws, or slide the plastic cover, if the design provides for its presence.
To successfully complete dismantling work, you will need a minimum set of tools that can be found in every home. The main tool will be a flathead screwdriver, but pliers and insulating tape can also come in handy. It is important to prepare the workplace: provide good lighting and free access to the rear wall of the unit.
- 🛠️ A small flat-head screwdriver for prying up the fasteners.
- 🔦 A flashlight for illuminating hard-to-reach places near the compressor.
- 🧤 Dielectric gloves to protect your hands from cuts and current.
- 📸 Smartphone for photographing the wiring diagram.
Before touching the parts, make sure that the power cord is unplugged from the outlet. In some refrigerator models, such as LG or Samsung, access may be complicated by the presence of additional plastic covers that must be carefully removed. Do not use excessive force to avoid breaking the plastic latches.
Procedure for turning off power supply and access
Safety is the number one priority when working with household appliances. Even if the refrigerator does not work and does not make sounds, this does not guarantee that there is no voltage in the circuit, especially if the thermostat or control unit is faulty. Complete de-energization eliminates the risk of a short circuit if the contacts are accidentally touched by a tool.
After disconnecting from the network, you must wait some time for the capacitors to discharge, if they are present in the control circuit, although in classic circuits with a starting relay this is less important than in inverter systems. However, a pause of 5-10 minutes will allow you to calmly inspect the compressor compartment without haste.
When removing the protective cover, pay attention to the condition of the wire insulation. If you find melted areas or cracks in the insulation, this may indicate overheating caused by a malfunction of that same relay or contact group. In this case, simply replacing the part may not completely solve the problem, and more in-depth diagnostics will be required.
⚠️ Attention: Never try to remove the relay while the compressor is hot. Allow it to cool completely after the last work to avoid burns and deformation of the plastic fastening elements.
In preparation for removing the panel, inspect the area around the compressor for moisture or oily stains. The presence of oil may indicate a freon leak from the system, which makes further repair of the relay pointless without calling a technician to recharge the system.
Design features of starting relays
Before you begin dismantling, it is useful to understand what exactly you are dealing with. Starting relays come in different types: electromagnetic and posistor. Electromagnetic ones are more often found in older models of refrigerators, such as Soviet ones ZIL or Biryusa, and posistor ones - in more modern units.
Externally, the relay is a plastic case, inside which the electrical filling is hidden. On one side, it fits over three contacts coming out of the compressor, and on the other, it has a connector for connecting the power wire. The shape of the case may differ: be square, rectangular or cylindrical, depending on the manufacturer.
| Relay type | Characteristic feature | Applicability | Dismantling features |
|---|---|---|---|
| Electromagnetic | Has a movable core | Old models | It is important not to drop the core |
| Posistor | Contains ceramic element | Modern models | Fragile, afraid of impacts |
| Combined | Combines protection functions | Universal | Complex shape housing |
Differences in design affect the method of attachment. Some relays are fixed only by a tight fit on the contacts, others may have an additional metal bracket or plastic clamp that covers the compressor housing. Determine the type of fastening visually before starting removal.
How does a posistor work?
A posistor is a semiconductor element whose resistance increases sharply when heated. At the moment of switching on, it passes current, starting the engine, and then heats up and opens the starting winding circuit, leaving only the main winding to work.
Step-by-step instructions: how to remove the relay
The process of removing the part requires accuracy and consistency. First you need to disconnect the wires going to the relay. Depending on the model, they can be connected via a header or soldered directly. If the wires are inserted into the terminals, they must be carefully pulled out, holding the relay itself so as not to pull it out along with the wires and damage the contacts.
If the wires are soldered, which is less common in modern models, you will need a soldering iron and solder. However, in most cases, including popular brands Bosch i Whirlpool, a detachable connection is used. After disconnecting the wires, proceed to removing the relay body itself from the compressor contacts.
☑️ Algorithm for removing the relay
The relay body sits tightly on the three pins of the compressor. To remove it, you need to grab the plastic case and, slightly shaking it from side to side, pull it up. Don't try too hard. If the relay cannot be removed, it may be fixed by a metal frame, which must first be bent or unscrewed.
In some cases, especially on old refrigerators, the relay may “stick” or get stuck due to oxidation of the contacts or vibration. In such a situation, you can carefully pry off the base with a flat-head screwdriver, but you must act extremely carefully so as not to damage the ceramic insulators of the compressor contacts.
⚠️ Attention: It is strictly forbidden to pull the relay by the wires. This will lead to breakage of the cores or damage to the internal contact group, which will make the part unsuitable for further use even after repair.
Diagnostics and visual inspection of the removed part
After the relay is in your hands, conduct a thorough visual inspection of it. Shake the part near your ear: if a ringing or knocking sound is heard inside, it means that the mechanical part is destroyed and the relay must definitely be replaced. A whole posistor or coil should not make sounds when shaken.
Inspect the contacts for carbon deposits, melting or oxidation. Black deposits on the contacts indicate poor contact and sparking, which could cause failure. If the plastic of the case is blackened or deformed, this is a clear sign of overheating and a short circuit inside the device.
For more accurate diagnostics, you can use a multimeter. Check the continuity of the circuit: in a cold state, the posistor should show low resistance, and when heated (if current is applied) it should break. The electromagnetic relay is checked for the absence of a break in the coil and the mobility of the core.
Also pay attention to the markings. Technical characteristics are usually indicated on the case: voltage, current, compressor type. This data is critical when selecting a new part. Using a relay with unsuitable parameters can lead to repeated breakdown or burning of the compressor windings.
Installing a new relay and checking operation
Installing a new or tested part is done in the reverse order. First, the relay is put on the contacts of the compressor. It is important to correctly orient the part: usually on the inside of the case or on the diagram there is an “Up” marking or an arrow indicating which side the relay should be facing up. Incorrect orientation may result in the mechanism not working.
After landing on the contacts, you need to connect the wires. If you photographed the circuit, there will be no problems. Make sure the terminals are tight and not loose. Weak contact will lead to heating and sparking, which will again disable the equipment.
The final stage is a test run. Plug in the refrigerator and listen. The compressor should start with a characteristic hum, which after a few seconds will turn into a smooth operating sound. If the startup was successful, you can replace the back cover.
| Symptom | Possible cause | Action |
|---|---|---|
| Clicking and silence | Faulty relay or compressor | Replace the relay |
| Humming and shutdown | Protection is activated | Check the relay and current |
| The refrigerator does not turn on | No power or thermostat burnt out | Check the circuit |
⚠️ Attention: If after replacing the relay the compressor hums but does not start within 3-5 seconds, immediately turn off the refrigerator. Long-term operation in this mode will burn the motor windings.
Frequently asked questions (FAQ)
Is it possible to repair an old relay rather than buy a new one?
Theoretically, electromagnetic You can try to disassemble the relay and clean the contacts from carbon deposits, but this is a temporary measure. PTC relays cannot be repaired because they are monolithic. Considering the low cost of a new part, repairing an old relay is not economically feasible and can be dangerous.
Why does the relay burn out repeatedly?
Frequent relay burnouts may indicate more serious problems: unstable voltage in the network, compressor wear (interturn short circuit) or problems with the thermostat, causing the compressor to work without interruption. In this case, simply replacing the relay will not solve the problem for a long time.
How to choose an analogue if the original is not on sale?
When selecting an analogue, focus primarily on the compressor power (indicated on the nameplate, for example, 1/5 HP, 1/4 HP) and the type of refrigerant. The geometric shape and location of the contacts are also important. Universal relays often have several pairs of contacts for different connection schemes.
Is it dangerous to leave the refrigerator operating without the back cover?
Short-term operation for testing is acceptable, but long-term operation without a cover is not recommended. The cover protects the compressor from dust, moisture and accidental mechanical damage, and also directs air flows for proper cooling of the engine.