Refrigerators Indesit series No Frost have earned popularity due to the absence of the need for manual defrosting, however, a complex air circulation system requires proper operation of all components. When the set temperature is no longer maintained in the chamber, and an ice coat forms on the back wall, most often the culprit is a faulty one heating element. It is he who is responsible for defrosting the evaporator automatically, and its failure blocks the operation of the entire cooling system.
Before calling a technician, you should try to diagnose it yourself, since replacing a part is often cheaper than service. To test, you will need a basic set of tools and an understanding of how an electrical circuit works. In this article, we will look in detail at how to identify a malfunction, what devices will be needed and what to pay special attention to when disassembling the unit.
Timely detection of the problem will avoid more serious breakdowns, such as compressor combustion due to overloads or food spoilage. It is important to understand that the system No Frost is a closed cycle, where each element influences the other. If the heating element does not heat, the evaporator becomes overgrown with ice, the fan stops, and the cold stops flowing into the chamber.
Symptoms of heater malfunction in the No Frost system
You can determine that the problem lies precisely in the defrost circuit by a number of indirect signs that appear long before the refrigerator completely stops. The first warning sign is often the appearance of ice on the back wall of the freezer, although the system is advertised as No Frost. The ice may be uneven, resembling icicles or a dense crust at the bottom of the evaporator.
The second obvious sign is ineffective cooling when the compressor is running. The unit hums, trying to gain temperature, but the thermostat does not turn it off, since the desired cold is not achieved. The fan in the chamber may work intermittently or make strange sounds, touching frozen ice with its blades.
⚠️ Attention: If you notice that the refrigerator turns on more often than usual and the temperature inside rises, do not ignore it. Long-term idle operation of the compressor can lead to costly repairs.
It is also worth paying attention to the operating mode. In a working refrigerator, cooling and defrosting cycles alternate regularly. If you hear the relay clicks, but there is no characteristic crackling of melting ice or the sound of water dripping into the drain pan, this is a sure sign that Defrost heating element does not perform its function.
Necessary tools and safety measures
To carry out For high-quality diagnostics, it is necessary to prepare tools in advance. The main device will be multimeterwhich will allow you to ring the circuit and measure the resistance. Without this device, the check will be of a mere nature, since it is impossible to visually determine the break of the spiral inside the sealed tube.
In addition to the measuring device, you will need screwdrivers (Phillips and flathead), possibly a ratchet wrench for removing panels, and a container to collect water. It would be a good idea to have a hairdryer ready if you need to speed up the defrosting of the ice before accessing the components, although in case of a full diagnosis this may not be necessary.
☑️ Preparation for diagnostics
Safety is the number one priority when working with electrical appliances. Before starting any work, including removing the rear panel, you must completely de-energize the refrigerator. Unplug the power cord and make sure there is no voltage. Residual current in capacitors can be dangerous, so let the equipment stand turned off for 10-15 minutes.
Working with wet hands or standing on a wet floor is strictly prohibited. If there is a lot of ice in the chamber, let it melt naturally or carefully remove mechanically, being careful not to damage the aluminum evaporator tubes and sensor wiring.
Access to the heating element: disassembling the freezer
To get to the heating element in refrigerators Indesit, you need to dismantle the back panel freezer compartment. The process may differ slightly depending on the specific model, but the general algorithm of actions remains similar. First you need to empty the chamber of food and remove all shelves and drawers.
Then the plastic panel covering the evaporator is removed. It is usually secured with latches and a few screws. Be careful with plastic elements: in the cold they become brittle and can crack if handled carelessly. If the panel is frozen, do not tear it off by force, it is better to warm it up a little with a hairdryer or wait until the ice melts.
After removing the panel, you will see the evaporator - a radiator with tubes wound around it and a heating element placed in the middle. In some models, the heater may be hidden under an additional layer of thermal insulation or a protective casing. Carefully bend the insulation to gain visual access to the contacts and body of the part.
Mounting features in different models
In some Indesit models, the heating element can be built directly into the aluminum groove under the evaporator. In such cases, replacement requires complete disassembly of the unit or the use of special repair kits, since simply pulling out the part will not work.
Visually inspect the heating element for obvious damage. Look for signs of corrosion, swelling, broken wires or melted insulation. However, even an ideal appearance does not guarantee serviceability, since a break can occur inside a sealed tube hidden from view.
Diagnostic methods with a multimeter
The most reliable way to check a heating element is to measure its electrical resistance. Switch the multimeter to resistance (Ohm) measurement mode, selecting a limit of 2 kOhm. Touch the probes to the heater contacts. If the spiral is intact, the device will show a value in the range from 200 to 400 Ohms, depending on the power of the specific model.
If a unit or an infinity symbol is displayed on the multimeter screen, this means open circuit. The spiral inside has burned out, and current does not pass through it. In this case, the part can only be replaced, it cannot be repaired. Zero or close to zero resistance indicates a short circuit, which is also a fatal malfunction.
It is also important to check the breakdown on the housing. Switch the device to the continuity test mode or resistance measurement mode to the maximum limit (megaohms). Press one probe to the contact of the heating element, and the other to the metal body of the heater or evaporator. The device should not react (show infinity). If there is at least some resistance, it means that the insulation is broken, and operating such a heating element is life-threatening.
Do not forget to also check the circuit up to the heating element itself. It often happens that it is not the heater itself that burns out, but the fuse (thermal fuse), which is located in the open circuit. It also needs to be ringed: a working fuse should “ring”, indicating zero Ohm.
Diagnostics of related elements of the defrost system
The problem with defrosting does not always lie in the heater itself. The circuit also includes defrost sensor (thermostat) and a timer (or electronic control module). If the heating element is working but does not turn on, the reason may be the sensor, which does not give the command to heat, “thinking” that there is no ice or, conversely, the temperature is already high.
The defrost sensor in a cold state should close the circuit (resistance is close to zero). If it “rings” only when heated or does not close at all, it must be replaced. You can check it by cooling it in the freezer or heating it with a hairdryer, monitoring the resistance with a multimeter.
| System element | Normal state (cold) | Normal state (warm) | Fault |
|---|---|---|---|
| defrost heating element | 200-400 Ohm | 200-400 Ohm | Infinity (break) |
| Thermal fuse | 0 Ohm (closed) | 0 Ohm (closed) | Infinity (burnt out) |
| Defrost sensor | 0 Ohm (closed) | Infinity (open) | Does not open when heating |
| Heating element insulation | Infinity | Infinity | There is resistance (breakdown) |
It is also worth checking the condition of the wiring. Often, in bends or near sharp metal edges, wires become chafed, causing a short circuit or breakage. Carefully inspect the entire visible part of the harness going to the evaporator.
Replacement of a faulty heater and assembly
If diagnostics confirmed the failure of the heating element, it must be replaced. In refrigerators Indesit tubular heaters are most often used, which are inserted into special grooves on the evaporator or placed on tubes. Carefully remove the old element, trying not to damage the aluminum radiator tubes, since their repair is complicated and requires soldering with special solder.
Install the new heating element in place, making sure that it fits tightly to the surface of the evaporator for effective heat transfer. Connect the wires, observing polarity (although it is not important for the heating element, a reliable connection is important). It is advisable to use original connectors or properly insulate the twists with heat shrink.
After replacement, assemble everything in the reverse order: return the insulation, secure the back panel, install shelves and drawers. Plug in the refrigerator and listen. After some time, the defrost cycle should begin (if it is planned by the program), or the unit will begin to gain cold.
⚠️ Attention: Specifications of spare parts may vary depending on the year of manufacture of your model. Always check the power and geometric dimensions of the new heating element with the markings of the old element before purchasing.
Observe the operation of the equipment for the first few hours. Make sure that no new layer of ice forms on the back wall and that water flows freely into the drainage hole. If everything works correctly, you can download the products.
Frequently asked questions (FAQ)
Is it possible to temporarily use a refrigerator without a heating element?
Theoretically, the refrigerator compartment will work, but the freezer will quickly become overgrown with ice, blocking the air circulation channels. This will cause the fan to stop and the temperature in all chambers to rise. Long-term operation without defrosting is harmful to the compressor.
Why does a new heating element burn out after a short time?
A common reason is a faulty defrost sensor or timer that does not turn off the heating on time, causing overheating. It is also possible that moisture gets on the contacts or the use of a low-quality analogue spare part.
Is it necessary to completely defrost the refrigerator before replacing?
It is advisable to let the ice melt so that water does not get on the electrical contacts and in the drainage, which may be clogged. However, you can urgently check the heating element on a frozen unit, using maximum caution.
What is the service life of the heating element in Indesit?
On average, the heating element lasts 5-7 years under normal operating conditions. Frequent power surges in the network or incorrect operation of other system components can significantly shorten this period.