The situation when the refrigerator stops freezingand a “coat” of ice is visible on the back wall of the chamber often indicates a malfunction of the defrost system. In modern models with No Frost, a heating element is responsible for this process, which is periodically turned on to melt the ice on the evaporator. If this unit fails, the ice blocks the circulation of cold air, and the equipment stops performing its functions.
Before calling a technician, you can carry out an initial diagnosis yourself. Checking the heating element is a procedure that is accessible even to a beginner with a minimum set of tools, for example, a multimeter. It is important to understand that the electric heating element is a consumable part and burns out over time, requiring replacement.
In this article we will analyze a step-by-step algorithm of actions that will help you determine exactly whether Defrost heating element is to blame for the breakdown of your refrigerator. We will look at visual inspection methods, circuit continuity rules and nuances that are often missed when independently repairing household appliances.
Symptoms of a heating element malfunction
You can understand that the problem lies in the defrosting system by the characteristic signs of the unit’s operation. Typically, the user notices that temperature in the chamber rises above normal, food begins to deteriorate, and the compressor works almost without interruption, trying to compensate for the loss of cold.
If you remove the back panel in the freezer, you can find a massive layer of ice or frost on the evaporator. In a working refrigerator with a No Frost system, the evaporator should be clean or covered with a thin, barely noticeable layer of frost. The presence of a “coat” indicates that defrosting cycle does not start or does not complete.
- ❄️ A thick layer of ice or a snow coat is visible on the back wall of the freezer.
- 🔊 The compressor is humming continuously, without characteristic rest breaks.
- 🌡️ In the refrigerator compartment, the temperature is higher than the set temperature, the food thaws.
- 💧 Water flows out from under the refrigerator or accumulates in the bottom drawer.
However, you should not immediately blame the heater. Similar symptoms may occur if the timer breaks down. That is why a comprehensive check of all circuit elements is a mandatory step before purchasing a new spare part. defrost thermostat or timer. That is why a comprehensive check of all chain elements is a mandatory step before purchasing a new spare part.
Preparation for diagnostics and safety precautions
Any work related to the electrical components of the refrigerator requires strict adherence to safety measures. The first and most important step is complete disconnecting the device from the power grid. Unplug the plug from the socket and make sure that access to the socket will not be blocked during operation.
To carry out diagnostics, you will need a basic set of tools. First of all, it is multimeter (tester) capable of measuring resistance and ringing a circuit. You will also need screwdrivers (Phillips and flathead) to dismantle the panels and, possibly, a hair dryer to quickly defrost the ice before removing the parts.
⚠️ Attention: Never try to chip the ice with a knife or sharp objects. Damage to the evaporator tubes will lead to a freon leak and expensive repairs that cannot be done at home.
Before disassembling, it is recommended to let the refrigerator stand unplugged for several hours so that the ice completely melts. If time is pressing, you can use a hairdryer, but you need to direct the flow of hot air carefully, without overheating the plastic elements of the case.
☑️ Preparing to check the heating element
Access to the heating element: dismantling the elements
Location of the heating element depends on the model and manufacturer of the refrigerator. In most cases Defrost heating element located in the freezer, directly under the evaporator. To get to it, you need to remove the back wall of the chamber.
The process begins with dismantling all drawers, shelves and guides that interfere with access to the rear panel. The mounting screws can be hidden under decorative plugs or plastic covers. Be careful: plastic becomes brittle in the cold, so all manipulations should be carried out carefully.
After removing the panel, the evaporator will be revealed to your attention. The heating element can be located underneath (in the form of an open spiral or in a quartz tube) or built-in (in an aluminum casing). In some models, for example Indesit or Atlant, the heating element may be located in the drainage hole or hidden behind additional thermal insulation.
To remove the part, it is often necessary to disconnect the wires. Before this, it is strongly recommended to photograph the connection diagram or mark the contacts with a marker so that during assembly you do not confuse the polarity or connections.
Visual inspection and search for external damage
The first stage of diagnosis is a careful visual inspection. Often a breakdown can be determined without the use of measuring instruments. If the heating element is an open spiral, inspect it for ruptures or melting.
In the case of heating elements in a quartz tube or aluminum casing, look for signs of swelling, cracks or blackening of the housing. The presence of such defects with almost one hundred percent probability indicates that the part has failed and requires replacement.
Also pay attention to the condition of the wires going to the heating element. Melted insulation or oxidized contacts may indicate a short circuit or poor contact, which will also interfere with the operation of the defrost system. If there are no visual defects, we proceed to an instrumental check.
Is it possible to restore a burnt-out heating element?
It is impossible to restore the integrity of a nichrome spiral or a sealed tubular heater at home. Trying to twist the ends of the wire will only lead to temporary and dangerous results. The only correct solution is to completely replace the unit with an original or high-quality analogue.
Checking the heating element with a multimeter: step-by-step instructions
The most accurate way to determine the performance of a part is to measure its electrical resistance. To do this, switch the multimeter to resistance measurement mode (Ohm, indicated by the Ω icon). It is better to choose a range within 2 kOhm (2000 Ohm).
Touch the probes of the device to the contacts of the heating element. If the part is working properly, the device will show a certain resistance value. For household refrigerators, the range from 200 to 500 Ohmis considered normal. The exact value depends on the power of the heater and its design.
If a unit (or an infinity symbol) is displayed on the multimeter display, this means open circuit. The heater has burned out and does not conduct electricity. In this case, replacement is necessary. If the device shows zero or a value close to zero, this indicates a short circuit inside the element.
Additionally, you should check the heating element for breakdown on the body. Set the multimeter to dial mode (usually indicated by a speaker icon). Press one probe to the contact of the heating element, and the second to the metal body of the part. The device should not emit a sound signal. If there is a “squeaking” sound, it means that there is a breakdown in the housing, which is dangerous to life during operation.
| Multimeter reading | Value | Actions |
|---|---|---|
| 200 - 500 Ohm | Normal (good) | Check thermostat and timer |
| 1 (infinity) | Open circuit (burnt out) | Replace the heating element |
| 0 Ohm | Short circuit | Replace the heating element |
| Sound when dialing on the body | Insulation breakdown | Replace urgently, operation is prohibited |
Diagnostics of related system elements
A frequent mistake is to replace only the heating element, when the cause of system failure lies in other components. The defrost circuit also includes thermostat (defrost sensor) and, in some models, a thermal fuse. If they are faulty, the current simply will not reach the heater, even if it is new.
The defrost thermostat should open the circuit when it reaches a certain temperature (usually about +10...+15°C) and close it when cooling. It also needs to be “ringed” with a multimeter. In a cold state (below +5°C), it should ring, indicating the presence of contact.
The thermal fuse serves to protect against overheating and burns out if the heating element is not turned off in time. The check is similar: there should be a resistance close to zero (the circuit is closed). If the fuse is broken, it also needs to be replaced.
- 🔍 Inspect the contacts of the defrost sensor for the presence of oxides.
- 🌡️ Check the resistance of the thermostat when cold.
- 🔗 Make sure the integrity of the wires connecting all elements circuits.
In modern electronically controlled refrigerators, diagnostics can be complicated by the presence of a control board. If all elements of the circuit are working, but the defrost does not turn on, the controller may have malfunctioned or the relay on the board has burned out.
Replacement of the heating element and typical assembly errors
If diagnostics confirmed a malfunction of the heater, it is replaced. When installing a new heating element, it is important to ensure tight contact with the evaporator. For tubular heaters, thermal conductive pasteis often used, which improves heat transfer and prevents local overheating.
When assembling, pay attention to the position of the wires. They should not touch moving parts of the fan or sharp metal edges that could damage the insulation when the refrigerator vibrates. Use standard clips and clamps for fixation.
⚠️ Attention: Do not plug in the refrigerator immediately after assembly if you defrosted it with a hairdryer or water. Make sure that all internal surfaces and electrical contacts are completely dry.
After completing the work and turning on the refrigerator, listen to its operation. After some time (depending on the timer or electronics settings) the defrost cycle should begin. You can verify this by touching the drainage tube at the outlet of the refrigerator - it should become warm.
How much does it cost to replace a heating element in a service center?
The cost consists of the price of the spare part and the work of the technician. The heating element itself costs from 500 to 2000 rubles, depending on the model. Diagnosis and replacement work costs on average from 1,500 to 3,000 rubles. Self-repair allows you to save on specialist labor costs.
Is it possible to temporarily operate a refrigerator without a heating element?
Technically, the refrigerator will freeze, but you will have to manually defrost it every 5-7 days. If you do not remove the ice yourself, it will build up on the evaporator, block the air channels, and the efficiency of the freezer will drop to zero. In addition, this will increase energy consumption.
Why did the new heating element burn out after a week?
Most often, the reason lies in a faulty defrost thermostat, which does not turn off the heating in time, leading to overheating. It is also possible that the spare part itself is defective or poor contact in the circuit, causing sparking and current surges.
Is it necessary to change the heating element together with the defrost sensor?
It is not necessary to change everything at once if diagnostics have shown that the sensor is serviceable. However, given that these elements work in pairs and have a similar resource, many craftsmen recommend replacing them in a comprehensive manner in order to avoid re-disassembling the refrigerator in the near future.
How often do you need to defrost a refrigerator with No Frost?
The No Frost system involves automatic defrosting, so forced defrosting is rarely required - usually once a year for hygienic cleaning. If you have to defrost more often, this is a signal of a malfunction of the defrosting system, which needs to be checked according to the instructions above.