Finding a fuse in the refrigerator LG often becomes a critical diagnostic step when the unit stops turning on or, conversely, refuses to turn off. Unlike consumer electronics with external power supplies, refrigeration products integrate protective elements directly into the compressor electrical circuit or control system. Understanding where exactly this element is located allows you to save time on calling a technician and independently carry out an initial diagnosis of the malfunction.
Most modern models LG with the system No Frost do not use a classic fuse in a glass bulb, but more complex thermal protective devices. They can be built into the start relay, located on the evaporator, or be part of the electronic control module. It is critically important to understand that in 90% of cases in LG refrigerators it is the evaporator thermal fuse that burns out, and not the main mains fuse. This is a key difference that determines the further search and repair strategy.
Before proceeding with disassembly, it is necessary to completely de-energize the device. Working on live electrical circuits is strictly prohibited and may result in electric shock or electronic failure. If you are not confident in your abilities, it is better to stop at the visual inspection stage. However, for those who decide to act on their own, then we will analyze in detail the algorithm for searching and checking protective elements in various components of the refrigerator.
Main types of protective elements in LG technology
In refrigerators of the Korean brand LG several levels of electrical circuit protection are used. The first level is the surge protector and fuse link, which are located in close proximity to the power cord. However, as repair practice shows, they rarely burn out, usually only with a direct lightning strike or a serious power surge in the general network.
The second and most important type is thermal fuse (thermal fuse). It is installed in the defrost heating element or fan circuit. Its task is to break the circuit if the temperature in the evaporator zone exceeds the permissible values (usually 72-77°C). This prevents the plastic from catching fire and food spoilage if the defrost relay sticks. The third type is thermal relay, built into the compressor starting device, which protects the motor from overheating of the windings.
- 🔌 Mains fuse: Located in the filter board or immediately after the cable entry, protects against short short circuit.
- 🔥 Thermal fuse: Located on the evaporator, it is triggered when the defrosting system overheats.
- ⚙️ Thermal relay: Part of the compressor starting kit, protects the engine from overloads.
It is important to note that in models with an inverter compressor, the protection circuit can be integrated into the electronic control unit located at the lower rear of the unit. In such cases, there may not be a separate replaceable fuse in the classical sense, and the protection function is performed by the electronics of the board.
Location of the fuse on the control board
Electronic control module in refrigerators LG most often located in the lower part of the rear wall, behind the protective cover. This is where the main electrical input to the device is located. To get to the board, you need to unscrew several screws and remove the metal or plastic casing. Inside you will see a green printed circuit board with radio components.
On the board itself, the fuse is a small element, often in a black or transparent case. It can be made in the form of a glass cone with metal contacts or a ceramic cylinder. In some models LG it is marked as FUSE or F1. If carbon deposits, blackening or breaking of the thread inside the glass are visually visible on the element, this is a sure sign of burnout.
⚠️ Attention: Replacing the mains fuse on the control board without eliminating the cause of the power surge will lead to re-burnout. Be sure to check the outlet and wiring in the house before installing a new element.
Often, along with the fuse on the board, other elements, for example, a varistor or diode bridge, burn out. Therefore, a simple replacement may not work if the board logic itself is damaged. In modern models with digital control, a blown fuse is often accompanied by a lack of indication on the front display.
Searching for a thermal fuse in the No Frost system
If The refrigerator LG has stopped freezing, but the compressor is still running, the problem most likely lies in the defrost system. In this case, we are not interested in the mains fuse, but in defrost thermal fuse. It is located directly on the evaporator, which is hidden behind the back panel inside the freezer.
To access it, you will need to completely defrost the refrigerator (at least 10-12 hours), remove all the shelves and dismantle the plastic back wall of the freezer. Below it you will see an aluminum evaporator radiator with wound copper tubes. The thermal fuse is usually secured with a clamp or clip on one of the fins of the evaporator or on the heating element itself.
Visually it looks like a small black or white capsule with two wires, often packed in heat shrink. Models LG often use fuses with a response temperature 72°C or 77°C. Their cold resistance should be zero (or close to it). If the multimeter shows infinity (one on the left side of the screen), then the element is burned out and requires replacement.
☑️ Diagnostics of the defrost system
It is worth considering that the combustion of this element is only a consequence. The cause is usually a malfunction of the defrost sensor or timer, which causes the heating element to heat for too long until the emergency protection is triggered. By simply replacing the fuse, you risk encountering the same problem again in a week.
Diagnostics of the starting relay and thermal protection of the compressor
The third important unit where the protection is located is the starting relay, mounted on the compressor housing in the lower rear part of the refrigerator. Here thermal protector (overheating protection) is installed. If the compressor hums for a few seconds, clicks and turns off, the problem may be here. Thermal protector To check, you need to remove the plastic casing from the relay (usually it is held on by latches or one screw). Inside you will see a black “pill” with two contacts - this is a thermal relay. It is put directly on the terminals of the compressor windings. In its normal state, it should “ring” (have zero resistance). LG It buzzes for a few seconds, clicks and turns off, the problem may be here.
To check, you need to remove the plastic casing from the relay (usually it is held on by latches or one screw). Inside you will see a black “pill” with two contacts - this is a thermal relay. It is put directly on the terminals of the compressor windings. In its normal state it should “ring” (have zero resistance).
If the relay is burned out, the compressor will not be able to start, since the power circuit will be broken. However, as in the case of a thermal fuse, combustion of the compressor thermal protection often indicates more serious problems: an interturn short circuit in the engine, jamming of the piston group, or a critical voltage drop in the network.
- 🛑 Symptom: The compressor tries to start, a hum is heard, then a click and silence.
- 🔋 Cause: Overheating of the windings or jamming of the motor mechanics.
- 🔧 Solution: Replacing the start relay (often sold complete with a capacitor).
Is it possible to remove the thermal protection?
It is strictly not recommended to remove the thermal protection from the circuit. Without it, if the compressor becomes jammed, it can burn out in a matter of minutes, and in the worst case, it can ignite, as the temperature of the windings reaches critical values.
Tools for checking and replacement
To carry out high-quality diagnostics, you will need a minimum set of tools. The main device is multimeter (tester). Without it, it is practically impossible to determine the integrity of the fuse visually, since the break is not visible inside the black capsule. You will also need screwdrivers (Phillips and flathead), pliers and, possibly, a soldering iron.
When purchasing a new fuse, it is important to strictly observe the ratings. For thermal fuses, the response temperature is critical. Installing an element with a higher temperature (for example, 90°C instead of 72°C) can lead to the fact that if the defrosting system malfunctions, the plastic inner lining of the refrigerator will have time to melt.
| Element type | Where it is located | Normal resistance | Failure sign |
|---|---|---|---|
| Mains fuse | Control board (bottom back) | 0 Ohm (Ringing) | The refrigerator does not turn on, there is no light |
| Thermal fuse | Evaporator (inside the freezer) | 0 Ohm (ringing) | Not freezing, ice is frozen, heating element is not heats |
| Thermal relay | Compressor starting device | 0 Ohm (ringing) | Buzzes and clicks, does not start |
| Fuse fan | Fan circuit (rarely) | 0 Ohm (ringing) | It makes noise, but does not cool |
When soldering a new thermal fuse, try not to overheat its soldering iron tip, as high temperature can activate the internal trigger mechanism before installation. Use flux and quickly connect the contacts.
Typical mistakes during self-repair
One of the most common mistakes is installing a “bug” - shorting the contacts of a burnt fuse with a wire. Do this strictly prohibited. The fuse is the weak link that saves your home from fire. If you close the circuit, during the next malfunction (for example, a short circuit of the heating element), the refrigerator wiring may melt and cause a fire.
The second mistake is ignoring the cause of combustion. Many users change the burnt thermal fuse, happily turn on the refrigerator, and after 3-4 days the situation repeats. This happens because it has not been verified defrost sensor. If the sensor “lies” and does not give a command to turn off the heating element, the new fuse will also burn out.
⚠️ Attention: Technical characteristics and location of parts may vary slightly depending on the specific model and year of manufacture of the refrigerator LG. Always check the technical documentation or the diagram on the product body before starting work.
Also often forgotten about high-quality insulation of solder points. In conditions of high humidity and temperature changes inside the refrigerator compartment, ordinary electrical tape can quickly peel off, leading to a short circuit. Use heat-shrinkable tubing and heat it with a hairdryer to securely fix it.
Frequently asked questions (FAQ)
Is it possible to temporarily turn on the refrigerator without a fuse?
No, this cannot be done. The absence of a fuse leaves the circuit unprotected. Any power surge or short circuit will burn out the wiring, control board or cause a fire. Operation without protection is dangerous.
Why does the fuse burn out immediately after replacement?
This indicates that the cause of the malfunction has not been eliminated. Most likely, the defrost heating element is faulty (short circuit), the defrost sensor, or there is a problem with the wiring. It is necessary to carry out a complete diagnosis of the system.
Where to buy an original thermal fuse for LG?
Original spare parts can be found in specialized stores of spare parts for household appliances, ordering according to the model of the refrigerator. Also suitable are universal analogues with similar characteristics (operation temperature and current), which are sold in radio parts stores.
How much does it cost to replace a fuse in the service?
The cost consists of the price of the part itself (usually inexpensive) and the work of the technician. However, calling a technician is often not economically feasible just to replace the fuse, if you can do it yourself with a multimeter.
How to understand that it is the fuse that has burned out and not the compressor?
You need to test the circuit with a multimeter. If the fuse rings (resistance 0), but the compressor does not start and hums, the problem is in the motor or start relay. If the fuse does not ring, it is burnt out. The compressor is usually checked by the resistance of the windings.