A sudden stop of the refrigerator or a characteristic hum without starting the compressor often indicates problems in the electrical circuit of the engine. Equipment owners Indesit face such situations regularly, and in most cases the culprit is the starting relay. This small but critical component is responsible for starting the motor and protecting it from overloads. If you notice that your Indesit refrigerator stops freezing or makes clicking noises but does not turn on, the likelihood of failure of this particular unit is extremely high.
Self-diagnosis does not require deep knowledge of electrical engineering, but requires compliance with safety precautions and the availability of a minimum set of tools. It is important to understand that ignoring symptoms can lead to more serious consequences, even burning out the compressor itself. In this article we will analyze in detail the design of the starting relay, the symptoms of its malfunction and a step-by-step algorithm for testing it with a multimeter. You will learn to determine whether a part needs urgent replacement or whether the problem can be solved in another way.
⚠️ Attention: Before starting any diagnostic or repair work, be sure to disconnect the refrigerator from the power supply. Working with electrical appliances under voltage is deadly.
Signs of a faulty starting relay
You can determine that the problem lies in the starting mechanism by a number of characteristic signs. Most often, the refrigerator Indesit begins to behave inappropriately: the motor tries to start, a loud click is heard, but after a few seconds it goes silent. This is a classic picture, indicating that starting relay cannot close the winding circuit to start the rotor. The compressor may be hot, as it is trying to work, but does not receive the desired impulse.
Sometimes the situation looks different: the unit hums, but does not start at all, or turns on only for a short time, after which it goes back into standby mode. In some cases, the relay may “stick” in the on state, which leads to continuous operation of the engine without stopping. This is dangerous because the compressor operates in overload mode, which drastically reduces its service life. If you hear frequent clicking sounds every few minutes, this is a sure sign that the thermal release is tripping due to a faulty starting element.
- 🔊 There is a loud click when trying to start, but the compressor does not start.
- 🔥 The compressor motor heats up, but the refrigerator does not cool the chambers.
- ⚡ The circuit breaker in the panel is triggered or the plugs are knocked out.
- 🔄 The engine starts for a few seconds, then stalls and tries to start again.
It is important not to confuse a relay malfunction with a breakdown of the compressor or thermostat itself. If, when you disconnect the relay from the compressor and shake the inside, you hear a rattling sound (like breaking glass), this is almost guaranteed to indicate destruction of the internal contacts. However, for an accurate diagnosis, a visual inspection is not enough; it is necessary to ring the contacts with the device.
Design and principle of operation of the relay
In order to carry out high-quality diagnostics, you need to understand how this unit works in refrigerators Indesit. The starting relay is a plastic case, inside of which there is an electromagnetic coil and a contact group. The operating principle is based on the passage of current through the motor windings. At the moment of starting, the current is high, the magnetic field of the coil draws in the core, closing the contacts of the starting winding, which allows the rotor to gain speed.
As soon as the engine reaches operating mode, the current drops, the core drops, opening the starting circuit. In parallel with this, thermal protection (thermal relay) often operates, which opens the circuit completely when the compressor overheats critically. Models Indesit often use relays of the R600 or RCTseries, which can be combined with thermal protection or made separately. Understanding this circuit will help you correctly interpret the multimeter readings.
Critical important: The relay is selected strictly for the power and characteristics of a particular compressor. Installing the wrong part, even with identical connectors, can result in immediate failure of the new component or damage to the motor windings. Always check the markings on the body of the old part with the catalog number of the new one.
Structurally, the device is divided into several key elements: input contacts for connecting phase and zero, output contacts going to the compressor windings, and a movable core. Impaired mobility of the core or burning of contacts are the main causes of failures. Over time, the plastic can melt and the contacts oxidize, which increases resistance and prevents normal starting.
What is the difference between a posistor relay and an electromagnetic one?
Electromagnetic relays (mechanical) use a starting current to retract the core and often make a clicking sound. PTC (solid-state) devices have no moving parts, operate silently and change resistance when heated. In older Indesit models, mechanical ones are more common, in new ones - posistor ones. Testing the posistor requires cooling it down (2-3 minutes) before retesting.
Preparation for diagnostics and necessary tools
Before starting disassembly, it is necessary to prepare the workplace and tools. You don't need sophisticated equipment; a basic home DIY kit is enough. The main condition is good lighting, since the back wall of the refrigerator, where the compressor is located, is often in a darkened area or filled with things.
To carry out the work you will need: a multimeter (tester) to measure resistance and check the continuity of the circuit, a screwdriver (Phillips or flat, depending on the fastening of the casing), pliers for removing terminals and, possibly, a knife for stripping contacts. If you are planning a replacement, purchase in advance a new relay that matches the marking of your unit Indesit.
- 🛠️ Multimeter (necessarily with continuity and resistance measurement mode).
- 🔧 A set of screwdrivers for removing the protective casing.
- 🧤 Dielectric gloves for additional security.
- 📱 Smartphone with a camera (to photograph the connection diagram before disassembling).
Start by disconnecting the refrigerator from the network. Move the unit away from the wall to gain access to the rear. Remove the protective cover of the compressor compartment, which is usually secured with latches or bolts. Under it you will see a black cylindrical compressor tank and a plastic box attached to it - this is our starting relay.
☑️ Ready for diagnostics
Dismantling and visual inspection of the part
Removing the relay is a simple process, but requires care. On most models Indesit it is simply put on the compressor terminals. First you need to disconnect the wires coming from the power cord and the thermostat to the relay. Be careful: the wires can be brittle from time and temperature, so avoid sudden jerks.
Carefully remove the relay from the compressor pins. It can fit tightly, so slight rocking from side to side is allowed. Do not use excessive force to avoid damaging the terminals of the motor itself. After removing the part, carefully inspect it from all sides. The presence of melted plastic, blackened areas or burn marks indicates a short circuit or overheating.
| Visual sign | Probable cause | Action |
|---|---|---|
| Melted body | Overheating of contacts, short circuit | Replacement is required |
| Rust on terminals | Moisture, oxidation | Cleaning or replacement |
| Cracks on plastic | Mechanical damage | Replacement is required |
| Rattling sound | Destruction of internal elements | Replacement is required |
If there is no external damage, this does not guarantee serviceability. The contacts inside could simply oxidize or burn out, leaving no visible marks on the outside. Therefore, we move on to instrumental verification. Before installing a new relay or returning the old one to its place, it is recommended to clean the compressor contact pads with fine sandpaper if they have oxides.
⚠️ Attention: If you find that the wires leading to the relay have damaged insulation or traces of melting, replace them or restore the insulation with heat shrink. Using damaged wiring is unacceptable.
Checking a relay with a multimeter
The most reliable way to find out the condition of a part is to ring it with a tester. Switch the multimeter to resistance measurement mode (Ohm) or continuity mode. First check the continuity between the input and output contacts. In the normal state (without voltage applied), the circuit can be open, since the relay only operates at a certain current.
However, if the relay is equipped with thermal protection, it should ring. Check the resistance between the thermal release contacts. If the device shows one (infinity) or zero (short circuit) where it should not be, the part is faulty. For electromagnetic relays, it is important to check the coil: the resistance should be within normal limits, usually from 30 to 60 ohms, depending on the model.
If you are able to apply safe low voltage voltage (for example, from a battery) to the coil, you can check whether the contacts click and close. But at home, they often focus on resistance and the absence of breaks. Compare the obtained values with the tabular data for your series of relays Indesit.
Pay special attention to checking for short circuits. Ring each relay contact relative to the housing. The device should not show any connection. If there is a breakdown in the housing, it is strictly prohibited to operate such a relay - this is a threat to life.
Replacement and startup of the system
If the diagnostics confirm the malfunction, a replacement is made. Install the new relay on the compressor terminals, observing the orientation (top/bottom indicated by the arrow UP). Reconnect the wires in the same order in which they were disconnected. Securely secure the terminals to prevent sparking.
After assembly, do not rush to close the back cover. Plug in the refrigerator and listen. The startup should be smooth, without loud clicks or buzzing. The compressor should pick up speed and run smoothly. If after 10-15 minutes of operation the motor is warm and the chambers begin to get cold, it means the repair was successful.
- ✅ Make sure that the arrow on the relay is pointing upward.
- ✅ Check the tightness of the terminals.
- ✅ Listen to the first cycle of operation for foreign objects noise.
- ✅ Reinstall the compressor compartment cover.
In some cases, after replacing the relay, it may take time to stabilize the operation of the refrigeration circuit. Let the unit operate for several hours without loading food to make sure the temperature is stable. If the problem is not solved, the compressor itself may be damaged or there is a freon leak.
Is it possible to repair the old relay rather than changing it?
Theoretically, if the problem is only in burnt contacts, they can be cleaned. However, in modern sealed relays Indesit this is almost impossible to do without destroying the housing. Even if it is possible to open and clean the contacts, the reliability of such work will be low. The cost of a new relay is low, so repairing the old one is impractical.
Why does a new relay burn out immediately after installation?
This indicates a more serious problem. Most often, the compressor itself is to blame (an interturn short circuit), which consumes too much current, or problems with the voltage in the network. Also, the reason may be a faulty thermostat, which does not allow the engine to rest, causing constant overloads.
Where can I find the relay markings to purchase a replacement?
The markings are usually applied to the side or top edge of the plastic case. Look for codes like R600, PTC, 100N or articles Indesit (for example, starting with C00). It is best to remove the old part and come to the store with it or take a photo for online ordering.
Is it dangerous to operate a refrigerator with a faulty relay?
Yes, it is dangerous. In addition to the risk of wiring fire due to overheating, there is a risk of compressor failure. Replacing a motor-compressor is a complex and expensive repair that requires evacuation of the system and charging with freon, which is often not economically justified compared to the cost of a new refrigerator.
How much does a starting relay cost for Indesit?
The cost of original and analog relays varies. Budget options can cost from 500 rubles, original spare parts Indesit - from 1000 to 2500 rubles. The price depends on the type of relay (with or without thermal protection) and the specific supplier of spare parts.