A sudden stop of the compressor or a characteristic clicking sound when trying to start are sure signs of a malfunction of the starting device in your Indesit. This small component is responsible for supplying a starting pulse to the motor windings, and without it, full circulation of the refrigerant is impossible. Fortunately, replacing the relay yourself does not require complex professional equipment and is accessible even to a beginner with a basic set of tools.
Before proceeding with dismantling, you need to make sure that the problem lies in this unit, and not in the compressor or thermostat itself. Often owners confuse the symptoms, which leads to the purchase of unnecessary spare parts. In this article, we will look at how to accurately diagnose a breakdown, what type of relay is installed in your model, and how to properly replace it so as not to damage the expensive motor.
It is important to understand that working with electrical appliances requires compliance with safety precautions, even if you do not open the cooling system. Improper operation may result in short circuit or electric shock. If you feel unsure of your abilities, it is better to contact the service center, but if the decision is made, follow each step of the instructions carefully.
Diagnostics of a malfunction of the starting relay
The first sign of failure starting relay is a characteristic sound: a series of clicks at intervals of several minutes, after which the compressor either does not starts, or starts for a split second and stalls. This happens because the starter is trying to apply voltage to the starting winding, but due to an internal breakdown, the circuits open prematurely. In some cases, the motor may hum, trying to start, which indicates a jammed rotor or lack of starting torque.
For accurate diagnosis, it is necessary to visually inspect the part. After removing the back cover and dismantling the relay, inspect its housing for signs of burning, melting or cracks. If a black coating is visible inside the case or there is a smell of burnt plastic, replacement is inevitable. It is also worth checking the contacts for oxidation, which often occurs due to condensation or temperature changes.
The most reliable way to check is to use a multimeter in dial mode. A working thermal relay should “ring” (show zero or resistance close to it) in a cold state. The starting relay is checked depending on its type: for induction relays the coil is checked, for posistronic relays the resistance of the posistor itself is checked, which should be in the range of 10-50 Ohms. If the device shows a break or infinite resistance, the part is faulty.
⚠️ Attention: Before any diagnostics, be sure to disconnect the refrigerator from the power supply! Residual voltage in the capacitors or accidental plugging into the socket during testing can lead to serious electric shock.
Sometimes the problem lies not in the relay itself, but in burnt contacts or a broken wire going to the compressor. Therefore, before purchasing a new spare part, make sure that the entire electrical circuit is intact. If no visual or instrument defects are found, but the refrigerator does not work, perhaps the problem is in the compressor itself, and replacing the relay will not help.
Choosing the appropriate spare part for Indesit
Refrigerators Indesit are equipped with various types of compressors, most often these are models from manufacturers Aspera, Embraco or Danfoss. Accordingly, starting relays may differ in design and electrical parameters. The main division occurs into induction (electromagnetic) and posistor (thermal) devices. Installation of the wrong type can lead to instantaneous burnout of the motor windings.
When choosing a new part, pay attention to the markings on the housing. Usually this is a set of numbers and letters, for example PTM-R or R600a. Parameters that are also important are: network voltage (usually 220V) and the type of refrigerant for which the compressor is designed. For modern models running on environmentally friendly freon R600a, relays with additional protection against sparking are often used.
The table below shows the main types of relays found in technology Indesitand their compatibility:
RT, RS
| Relay type | Marking (example) | Compatible compressors | Features |
|---|---|---|---|
| Posistor | PTM-R, R600a | Aspera, Embraco | Works silently, has no moving parts |
| Induction | Danfoss, old Aspera | Has a movable core, makes a click | |
| Combined | 100-150 W | Universal | Combines starting and thermal protection |
If the original spare part cannot be found, you can use universal analogues, but only if the compressor power matches. Universal relays often come complete with adapters for different types of plugs. However, for long-term and stable operation of the refrigerator Indesit it is better to look for original components or proven analogues from well-known brands, such as Zanussi or Electrolux, which are often interchangeable.
Is it possible to use a relay from another brand?
Yes, possible if the electrical parameters and mounting dimensions match. However, it is important to ensure that the type of protection (thermal or electromagnetic) matches the requirements of your compressor. Incorrect selection can lead to overheating of the motor.
Necessary tools and preparation
To successfully replace the start relay, you do not need bulky equipment. A minimal DIY kit, found in any garage or toolbox, is enough. The main thing is to ensure good access to the rear of the unit and sufficient lighting of the working area, since the space behind the compressor is often limited.
You will need the following tools:
- 🔧 Screwdrivers: flat and Phillips (for removing the casing and clamps).
- 🔪 Knife or scalpel (for carefully cleaning the contacts, if necessary).
- 🧤 Dielectric gloves (for additional safety when working with electricians).
- 📸 Smartphone (for photographing the connection diagram before disassembling).
The preparatory stage includes defrosting the refrigerator compartment if a lot of ice has accumulated in it, although for access to the compressor, complete defrosting is not always necessary. However, if you plan to work for a long time, it is better to free up space around the equipment. It is also recommended to move the refrigerator away from the wall by at least 50-70 cm in order to sit comfortably in the back.
☑️ Ready for repair
Removing the old start relay
The removal process begins by removing the protective plastic cover covering the compressor. It is usually secured with latches or screws. Be careful, the plastic becomes brittle over time and may crack if not handled carefully. After removing the cover, you will see a black “barrel” of the compressor, to the bottom of which the desired device is attached.
The relay is fixed on three contact pins of the compressor and can additionally be held on a metal bracket or a plastic retainer. Carefully remove the retaining bracket, if present. Then, holding the relay body, rock it from side to side (but without applying excessive force up and down) and remove it from the contacts. Sharp jerks can break the ceramic insulators inside or damage the contacts.
After dismantling, carefully inspect the seat on the compressor. There should be no traces of moisture, oxides or soot. If the contacts on the compressor itself are blackened, they must be carefully cleaned with fine sandpaper or a file until they have a metallic shine. This will ensure reliable contact and prevent sparking in the future.
⚠️ Attention: It is strictly forbidden to remove the relay by pulling the wires! This may lead to a break in the internal wiring or separation of the contacts from the relay body, which will make the new part unsuitable for installation.
Installation of a new component and assembly
Installation of a new one start relay is performed in the reverse order of dismantling. First of all, make sure that the new device is oriented correctly: the case often has marking UP or an arrow pointing up. Incorrect orientation may result in the mechanism not working or operating intermittently.
Push the relay onto the three pins of the compressor until it stops. It should fit tightly, without backlash. If the footprint is different in shape, you may need to use an adapter, which is sometimes included with universal relays. Make sure that the wires do not touch hot parts of the compressor or sharp edges of the metal frame.
After connecting, secure the relay with a retaining bracket or spring. Replace the compressor guard and secure it securely. Now you can proceed to the test run. Turn on the refrigerator and listen: there should be one confident click, followed by the smooth hum of a running motor.
Checking performance and common errors
After assembly, you need to check the operation of the refrigerator for 15-20 minutes. Pay attention to the temperature of the relay housing: during operation it may heat up, but should not be hot. If you feel intense heat or a burning smell immediately after turning it on, immediately turn off the equipment - it means that the wrong power was selected or an error was made during installation.
A common mistake for beginners is to ignore the state of thermal protection. If the relay has a bimetallic fuse, make sure it fits snugly against the compressor housing for correct temperature reading. Loose contact will result in the protection not working if overheated, which threatens to burn out the windings.
It is also important to check whether the wires are pinched by the fastening clamp. Vibration from a running compressor can wear down the insulation over time, leading to a short circuit to the housing. All connections must be free, but securely fixed in their sockets.
⚠️ Attention: If after replacing the relay the compressor starts, but after 10-15 seconds there is a click and shutdown again, the problem may not be in the relay, but in an interturn short circuit of the motor windings or mechanical jamming. Further attempts to start may finish off the motor.
Questions and answers (FAQ)
Is it possible to repair a burnt-out relay or just replace it?
Theoretically, a posistor relay can be disassemble and replace the ceramic element, but in practice this is not economically feasible. The cost of a new spare part is low, and the reliability of the restored device will be questionable. Induction relays cannot be repaired.
Why does a new relay burn out after a few days?
This may indicate an unstable voltage in the network, problems with the compressor itself (difficult starting) or incorrect selection of relay power. Also, the cause may be poor contact in the electrical circuit of the refrigerator.
What is the difference between the relay for R134a and R600a?
The main difference is the design of the contacts and the level of intrinsic safety. Freon R600a (isobutane) is explosive, so relays for such systems must be sealed or have special protection against sparking. Using an unsuitable relay is dangerous.
How long does it take to replace a relay?
For an experienced technician, the process takes 10-15 minutes. For a beginner, taking into account the preparation of tools, dismantling the cover and careful installation, everything can take about 30-40 minutes.
Do you need to call a technician for a replacement or can you do it yourself?
Replacing the start relay is one of the simplest operations in repairing refrigerators, which does not require evacuation of the system or working with gas. If you have basic skills and follow safety precautions, you can do this yourself.