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LG microwave not heating
Common reasons your LG microwave is not heating
The most common reasons your LG microwave is not heating are a bad thermostat, malfunctioning electronic control board or a broken switch.
43% of the time it's the Thermostat
23% of the time it's the Electronic Control Board
15% of the time it's the Switch
19% of the time it's the Something else
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Most common repairs needed to fix a LG microwave
Thermostat Replacement
A bad thermostat in a microwave will cause a variety of issues, mainly with power to the components of the microwave. Microwaves have several internal thermostats that protect you from harm when components inside the microwave fail. Many microwaves have a magnetron thermostat that trips when it detects high current going to the magnetron or high temperature in that area of the microwave cavity. Another thermostat monitors the temperature of the cooking cavity and trips when high temperatures occur. If any of these thermostats trip, the microwave won’t start, lights and fans will be inoperative and the display will be blank. Because microwaves contain a high-voltage transformer and high-voltage capacitors that retain a lethal amount of electricity even with the microwave unplugged, a Sears Home Services professional should examine the microwave and perform the repair.
Electronic Control Board Replacement
If a microwave electronic control board is malfunctioning, it can lead to various failures in the microwave, including a lack of power or heating, or it could prevent the microwave from turning off. This is because the board serves as the brain of the microwave, controlling crucial components such as magnetron the heats food, cooling fans, lights, the turn-table motor, cooking times and power level settings and the display. If the electronic control board malfunctions, it can disrupt communication between many different components. A failing board may cause a chattering or clicking noise or emit a burning odor. Due to the potential impact on multiple components, it is advisable to have a Sears Home Services professional conduct diagnostic tests on the board to confirm if replacement is necessary.
Switch Replacement
A broken switch in a microwave will cause a variety of issues, mainly with power to the components of the microwave. Microwaves have several internal thermal switches and interlock switches that protect you when components inside the microwave fail. Door interlock switches prevent the microwave from running when the door is open so you aren’t exposed to harmful radiation. Many microwaves have a magnetron thermal switch that trips when it detects high current going to the magnetron or high temperature in that area of the microwave cavity. Another thermal switch monitors the temperature of the cooking cavity and trips when high temperatures occur. If any of these switches fail, the microwave won’t start, lights and fans will be inoperative and the display will be blank. Because microwaves contain a high-voltage transformer and high-voltage capacitors that retain a lethal amount of electricity even with the microwave unplugged, a Sears Home Services professional should examine the microwave and perform the repair.
What to expect when you experience an LG microwave not heating issue
How is the not heating problem fixed?
Correcting most not heating problems usually involves replacing the thermostat, electronic control board or switch. However, there are many potential causes, so a thorough diagnosis is key to fixing the problem. An accurate diagnosis is essential to understanding how much the repair will be.
Sears Home Services recommendations for a microwave that is not heating
When the microwave is not heating it can be for many reasons. To avoid replacing unneeded parts we recommend having a Sears Home Services professional perform diagnostic tests to identify the root cause of the problem. Our technicians are experienced at diagnosing all types of microwave failures.
What to look out for with a microwave not heating diagnosis
Diagnosing modern appliances without proper knowledge and training can be difficult. Without using proper diagnostic techniques, fixing your microwave problem will only be achieved through changing parts on a hunch. Appliances, especially in the last 10 years, have become extremely advanced, and many models have electronic parts that are difficult to test. DIY repairs on the latest appliance models are becoming increasingly difficult.
LG Microwave is not Heating: Expert Troubleshooting Tips
When your LG microwave is not heating, check the control settings to make sure the microwave is set on an appropriate heat setting.
If the heat setting is adjusted properly and the LG microwave is not heating, a blown fuse, bad inverter board, failed magnetron, defective electronic control board, tripped high-temperature limit switch or wiring failure could be preventing the unit from heating. You’ll typically need to have a service technician diagnose and repair these types of intern microwave problems. Repairing a microwave yourself can be dangerous because internal components such as high-voltage capacitors can retain a lethal electrical charge even when the power cord is unplugged. Additionally, interlock switches need to be checked and the microwave needs to be checked for radiation leakage following any internal repair.
Schedule microwave repair service and we’ll send a Sears Home Services technician to your home to fix your appliance. We’ll get your microwave going again in no time.
Why is my LG microwave working but not heating?
When your LG microwave is running but not heating, a tripped thermal fuse or safety thermostat may be the cause of the problem.
A microwave has several of these safety devices that prevent the magnetron from working if the microwave overheated or drew too much electrical current. Overheating can be caused by a stuck relay and the microwave can draw too much electric current when a wire or component shorts out.
When you discover that your LG microwave is running but not heating, schedule repair service and we’ll send a Sears Home Services technician to your home to fix the problem.
Can you reset an LG microwave?
Yes. Unplug the microwave for 2 minutes and then plug it back in to restore power. The electronic control board in the microwave will reboot and reset. Reset the time on the display and test the microwave to see if it works properly.
Here’s a video that provides more details on resetting an LG microwave:
If the microwave still doesn’t work properly after resetting it, schedule service and we’ll send a Sears Home Services technician to your home to fix the problem.
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microwave
Mark really went over the microwave trying to fix it, this was his second time here for the same problem. August till ? till we get it replaced. we appreciate him for his knowledge of his job. thank you Mark
H M, Cadiz, OH
Customer
Mr. David is very polite and intelligent gentlemen. He came to replace a part on my microwave and he checked the microwave to make sure it was working properly. Mr. David gave me a courtesy call that he will be arriving in 15mins. He arrived on time for the appointment and took care of his job duties. Thanks Mr. David for all the hard work you do at Sears. Keep up all the good work.
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Frequently Asked Questions
Repair Microwave Resources
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Is it worth repairing a microwave? Find out the pros and cons of repairing your microwave at Sears Home Services.
Glossary Terms
A microwave diode is an electrical component that allows current to flow in one direction only, playing a crucial role in converting incoming electrical power into the microwave energy that cooks the food.
A microwave sensor is a technologically advanced feature in modern microwave ovens that measures vapor (steam) emitted by the food, adjusting the cooking time and power levels automatically for optimal results.
A microwave waveguide cover is a small, often mica or plastic piece inside the microwave that covers the opening where microwaves enter the cooking chamber, protecting the microwave's internal components from food splatter and ensuring efficient distribution of the microwaves.
A microwave magnetron is a component in microwave ovens that generates the microwaves used to cook food.