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Frigidaire microwave not heating
Common reasons your Frigidaire microwave is not heating
The most common reasons your Frigidaire microwave is not heating are a bad thermostat, malfunctioning electronic control board or a broken switch.
38% 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
24% of the time it's the Something else
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Most common repairs needed to fix a Frigidaire 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 a Frigidaire 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.
Why is my Frigidaire microwave running but not heating?
When the turntable rotates and the fan runs but the microwave doesn’t heat, it’s possible that an internal fuse has blown. There are several types of fuses that can prevent the microwave from heating. The magnetron fuse will prevent the magnetron from getting power needed to heat the microwave. A control board fuse will prevent the electronic control board from sending power to microwave parts that produce heat in the microwave cavity. A thermal fuse keeps the microwave from drawing too much current when a short occurs. The thermal fuse prevents the microwave from heating in some models. The wiring diagram for your microwave shows the various fuses in your model.
When a fuse blows and the microwave won’t heat even though it runs, you may be tempted to fix the problem by replacing the blown fuse yourself. Because of the dangers of attempting a DIY microwave repair noted above, we highly recommend that you have a service technician diagnose and repair a heating failure. A service tech will safely discharge the capacitor and check the heating components before replacing the fuse. The technician will also check for radiation leakage using proper testing equipment after completing the repair.
Don’t risk your life or health by attempting a DIY microwave repair. It’s not worth it. If your microwave stops heating and you can resolve the problem using basic troubleshooting described here or in the owner’s manual, have the microwave repaired by a professional service provider such as Sears Home Services or replace the microwave.
What is the average life of a Frigidaire microwave?
Most Frigidaire microwaves last an average of about 8 to 10 years with proper cleaning and maintenance.
Make sure that you properly clean the inside of the microwave cavity regularly to avoid arcs and sparks that can scar the inside liner. A damaged liner can cause the microwave to trip a fuse and stop heating or cause premature failure of other parts in the microwave so that it doesn't last as long as expected.
If you do see arc marks inside the microwave, follow the steps in this video to touch up arc marks yourself if they’re small enough to repair:
Keeping your Frigidaire microwave clean and repairing small arc and burn marks will help lengthen its lifespan.
If you find arc or burn marks too large to touch up on your own, you’ll likely need to have a Sears Home Services technician repair the microwave or you’ll need to replace the unit.
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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
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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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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.