The situation when the refrigerator Indesit stops cooling, and the light is on inside, often indicates a malfunction of the start-up relay or the compressor itself. The owner of the equipment is faced with a dilemma: call a technician or try to diagnose the problem himself. Self-checking the motor without connecting the standard relay is the most accurate way to understand whether unit is alive or needs to be changed.
It is important to understand that the standard relay in refrigerators Indesit can fail for various reasons, and often it is this one “Guilty” is assigned first. However, in order not to spend money on a new part and not get a non-working refrigerator back, you need to make sure the integrity of the motor windings. Electric motor is the heart of the system, and its diagnosis requires compliance with safety precautions and care.
In this article we will analyze in detail the methods of direct starting and testing the windings with a multimeter. You will learn how to distinguish a burnt out motor from faulty starting equipment. Diagnostics will allow you to save a significant amount on calling a specialist if you are ready to act carefully and consistently.
Preparation of the workplace and safety measures
Before touching inside the refrigeration unit, it is necessary to completely de-energize the device. Unplug the socket and move the refrigerator away from the wall, allowing easy access to the rear storage compartment. Working with electricity and refrigerant requires absolute sobriety and dry hands.
You will need a minimum set of tools that any home craftsman will have. The main device will be multimeter (tester) capable of measuring resistance in Ohms. You will also need a flathead and Phillips screwdriver, pliers and, possibly, electrical tape to temporarily isolate the contacts.
⚠️ Attention: It is strictly prohibited to carry out any manipulations with electrical components while the power cord is plugged in. The risk of electric shock when checking the compressor is extremely high due to the accessibility of metal parts of the housing.
Remove the rear metal cover covering the compressor area. In models Indesit it is usually secured with four bolts or latches. You will see a view of a black barrel-shaped motor-compressor, a condenser grille and a plastic box covering the contact group.
Removing the start relay and access to the contacts
To check the compressor without a relay, it must be carefully removed. At the end of the motor there is a plastic block containing a starting and protective relay. In refrigerators Indesit most often a relay type is used RT or its modern analogues.
First, take a photo of the location of the wires so as not to confuse the contacts during assembly. Then carefully remove the retaining bracket or bend the spring clips holding the relay to the compressor terminals. Movements should be progressive, without sudden jerks, so as not to damage the fragile copper terminals.
☑️ Check before removing the relay
After dismantling the relay, you will see three leads protruding from the compressor housing. They are arranged in a triangle. The two lower terminals are the ends of the working and starting windings, and the upper (or side, depending on the model) are general contact. It is to these contacts that we will connect the multimeter probes.
Visual diagnostics and search for external defects
Before picking up measuring instruments, conduct a thorough visual inspection. Often the cause of the malfunction is visible to the naked eye. Pay attention to the condition of the leads: if they are blackened, melted or oxidized, this is a sign of overheating or poor contact at the junction with the relay.
Inspect the compressor housing itself. The presence of oily smudges in the lower part of the unit or on the tubes coming out of it indicates depressurization of the system. If oil has leaked from the compressor, it means that the integrity of the freon circuit has been compromised, and such a unit cannot be repaired at home span>Smell the area around the motor. A sharp smell of burning or burning plastic indicates an interturn short circuit in the windings or a burnt out relay. If there is no smell and there are no visual defects, we proceed to an instrumental inspection.During a visual inspection, pay attention to the color of the copper tubes. If they are bright red, the system is sealed. If a greenish coating or black oxides are visible, there is likely a freon leak in this place.Testing the windings with a multimeter for resistanceThe most reliable way to check the integrity of the electrical circuit is to measure the resistance of the windings. Switch the multimeter to resistance measurement mode (200 Ohm or 2 kOhm range). First, check each terminal for breakdown to the housing: touch one probe to the cleaned area on the compressor housing (where there is no paint), and the other to each of the three contacts in turn.If the device shows one (infinity), this is good, it means there is no breakdown to the housing. If the multimeter beeps or shows a specific resistance value, it meansthat it is dangerous to operate such a compressor.the insulation is brokenNow we measure the resistance between the terminals themselves. For different modelsthe values may differ, but the general pattern remains the same. The resistance between the common terminal and the working winding is usually 10-25 Ohms, and between the common and starting windings it is 30-50 Ohms. The resistance between the starting and working windings should be the sum of these two values.Pair of contactsNormal resistance (Ohm)What does deviation meanCommon - Working10 - 25 OhmOpen or short circuitGeneral - Starting30 - 50 OhmOpen or short circuitWorking - StartingThe sum of the two is higherIncorrect measurementsAny - HousingInfinity (1)**Insulation breakdownIf the multimeter shows infinity between the terminals of the windings, which means in the circuit. If the resistance is close to zero, a short circuit has occurred. In both cases, the compressor requires replacement.breakWhy do the winding resistances differ?The working winding is wound with a thicker wire and has fewer turns, so its resistance is lower. The starting winding is designed for short-term operation and has a higher resistance, which creates the necessary phase shift to start the engine.Method of direct start of the compressorIf checking with a multimeter did not reveal any breaks, but the relay has failed, you can try to start the motor directly. This method allows you to eliminate malfunction of the starting equipment. To do this, you will need a piece of wire with a plug and, preferably, a button to open the starting winding circuit, although experienced craftsmen can do without it, using extreme caution.The connection diagram is simple: one wire from the plug (phase) is connected to the common terminal of the compressor. The second wire (zero) goes to the working winding. To start, you need to briefly apply voltage to the starting winding. When turned on, the motor hums, and if you give an impulse to the starting winding, it should start working.⚠️ Attention: When starting directly, there is a high risk of electric shock and damage to the compressor if the phasing is incorrect. Do not hold the wires with your hands while applying voltage. The duration of voltage supply to the starting winding should not exceed 1-2 seconds, otherwise it will burn out.If, after briefly closing the contacts of the starting winding, the compressor starts and runs smoothly, without making any extraneous sounds, then the motor itself is working. The problem lay in the relay. If the motor hums, jerks, but does not start, or knocks out the machines in the dashboard, it is most likely jammedor an inter-turn short circuit has occurred.piston mechanism.
Smell the area around the motor. A sharp smell of burning or burning plastic indicates an interturn short circuit in the windings or a burnt out relay. If there is no smell and there are no visual defects, we proceed to an instrumental inspection.
Testing the windings with a multimeter for resistance
The most reliable way to check the integrity of the electrical circuit is to measure the resistance of the windings. Switch the multimeter to resistance measurement mode (200 Ohm or 2 kOhm range). First, check each terminal for breakdown to the housing: touch one probe to the cleaned area on the compressor housing (where there is no paint), and the other to each of the three contacts in turn.
If the device shows one (infinity), this is good, it means there is no breakdown to the housing. If the multimeter beeps or shows a specific resistance value, it means the insulation is brokenthat it is dangerous to operate such a compressor.
Now we measure the resistance between the terminals themselves. For different models Indesit the values may differ, but the general pattern remains the same. The resistance between the common terminal and the working winding is usually 10-25 Ohms, and between the common and starting windings it is 30-50 Ohms. The resistance between the starting and working windings should be the sum of these two values.
| Pair of contacts | Normal resistance (Ohm) | What does deviation mean |
|---|---|---|
| Common - Working | 10 - 25 Ohm | Open or short circuit |
| General - Starting | 30 - 50 Ohm | Open or short circuit |
| Working - Starting | The sum of the two is higher | Incorrect measurements |
| Any - Housing | Infinity (1)** | Insulation breakdown |
If the multimeter shows infinity between the terminals of the windings, which means in the circuit break. If the resistance is close to zero, a short circuit has occurred. In both cases, the compressor requires replacement.
Why do the winding resistances differ?
The working winding is wound with a thicker wire and has fewer turns, so its resistance is lower. The starting winding is designed for short-term operation and has a higher resistance, which creates the necessary phase shift to start the engine.
Method of direct start of the compressor
If checking with a multimeter did not reveal any breaks, but the relay has failed, you can try to start the motor directly. This method allows you to eliminate malfunction of the starting equipment. To do this, you will need a piece of wire with a plug and, preferably, a button to open the starting winding circuit, although experienced craftsmen can do without it, using extreme caution.
The connection diagram is simple: one wire from the plug (phase) is connected to the common terminal of the compressor. The second wire (zero) goes to the working winding. To start, you need to briefly apply voltage to the starting winding. When turned on, the motor hums, and if you give an impulse to the starting winding, it should start working.
⚠️ Attention: When starting directly, there is a high risk of electric shock and damage to the compressor if the phasing is incorrect. Do not hold the wires with your hands while applying voltage. The duration of voltage supply to the starting winding should not exceed 1-2 seconds, otherwise it will burn out.
If, after briefly closing the contacts of the starting winding, the compressor starts and runs smoothly, without making any extraneous sounds, then the motor itself is working. The problem lay in the relay. If the motor hums, jerks, but does not start, or knocks out the machines in the dashboard, it is most likely jammed piston mechanism or an inter-turn short circuit has occurred.
Analysis of the operation of a running engine
A successful launch is only half the battle. It is necessary to evaluate the quality of operation of the unit. A working compressor Indesit works quietly, with a uniform hum. Body vibration should be minimal. Any knocking, metal clanging or sudden changes in sound tone indicate mechanical wear of the components.
Pay attention to the temperature of the case. In the first 5-10 minutes of operation, it may warm up slightly, but should not become hot. If after a short time the hand does not tolerate touching the metal, it means that there is interturn short circuitin the windings, which was not detected during a cold test.
Also check whether the compressor creates a vacuum at the inlet and pressure at the outlet. Place your finger on the inlet (suction) - it should stick, and on the outlet (discharge) you should feel a strong air flow. Weak draft indicates wear of the valve group.
Frequent diagnostic errors and their consequences
Beginners often make mistakes that lead to the final breakdown of the equipment. One of the most common is trying to run the compressor through an extension cord or weak socket. Inrush currents are high, and poor contact at the junction of the plug and socket can cause melting or false operation of the protection.
Another mistake is ignoring the cooling time. If you tried to start the engine several times, it got hot. The thermal relay (if it still functions somehow) or internal protection will prevent it from starting until it cools down. Give the unit 30-40 minutes rest before new attempts.
Do not forget about condensation. Moisture that gets onto the contacts or inside the terminal box can create a conductive bridge that will distort the results of resistance measurements. All contacts must be dry and clean.
⚠️ Attention: Technical characteristics of compressors may vary slightly depending on the year of manufacture and the specific series of the Indesit refrigerator. Always check the markings on the nameplate located on the motor housing to clarify the rated currents and type of refrigerant.
Is it possible to replace the compressor with an analogue one?
Yes, you can install compressors from other manufacturers (Danfoss, Secop, Embraco) if the overall dimensions and seating are the same openings, capacity and type of refrigerant. However, it is better to look for the original or a complete analogue by catalog number.
Final summary and decision making
Checking the refrigerator compressor Indesit without a relay is a procedure accessible to anyone who knows how to hold a screwdriver and a multimeter. It allows you to clearly divide the area of responsibility: either a cheap relay has burned out, or an expensive motor replacement is required.
If measurements show a break or breakdown, or direct starting is impossible, get ready to replace the unit. This is a complex procedure that requires evacuation of the system and charging with freon, which cannot be done without special equipment. In this case, self-repair is limited to diagnostics only.
If the motor is working properly, buy a new starting relay corresponding to the power of your compressor (indicated on the marking), install it and enjoy a working refrigerator. Remember that high-quality diagnosis saves money and time.
What to do if the resistance of the windings is normal, but the compressor does not start?
If the electrical part is intact, but there is no start, most likely, a mechanical jamming of the piston has occurred groups. Sometimes the “wedging” method helps by applying increased voltage (220V) to the working winding for a split second, but this is risky. Often such a compressor cannot be saved.
Is it possible to drive with an Indesit refrigerator plugged in?
Absolutely not. Transportation of a working or simply plugged-in refrigerator is prohibited. Oil from the compressor can leak into the freon circulation circuit, which will lead to clogging of the capillary tube and failure of the system immediately after switching on.
Which multimeter is better to choose for diagnostics?
For household needs, any entry-level digital multimeter with a continuity function and resistance measurement up to 20 kOhm is suitable. Expensive professional models are not required here, only the accuracy of the readings in the low resistance range is important.
Why does the compressor hum, but does not start without a relay?
The hum means that current is supplied to the working winding, and a magnetic field is created, but there is not enough torque to start. This may be due to the lack of a pulse to the starting winding (faulty relay or capacitor) or due to a mechanical wedge.