Microwave Blown Fuse Symptoms – DIY Appliance Repairs, Home Repair Tips and Tricks

DISCLOSURE: This post may contain affiliate links, meaning when you click the links and make a purchase, we receive a commission at no extra price to you Like all electrical appliances, microwaves rely on fuses to operate safely. Often refer to as ‘ sacrificial ’ components, fuses are meant to blow when the function conditions become insecure, thereby protecting the microwave and whoever might be using the appliance. But why does this happen ?
The reason that a microwave fuse blows depends mainly on when it happens. Suppose the fuse blows when you press Start; that means the high-voltage capacitor inside may have shorted out. But if the fuse blows when you open or close the microwave door, the cause could be a faulty door switch instead.
In this article, we ’ re going to explore everything you need to know about these symptoms when microwave fuses coke. We ’ ll besides explore a few critical questions surrounding microwave fuses.

Microwave Blowing Fuse When Press Start

Suppose your microwave fuse blows precisely when you press Start. If that ’ s the case, the causal agent may be a short-change high-octane capacitor .

Shorted High-Voltage Capacitor

What it is: Simply put, a capacitor is an electric component that stores or condenses electricity before releasing it into the microwave ’ s electric circuit .

In a way, a capacitor is reasonably like a battery. still, there is one significant remainder : a capacitor is designed to charge and discharge its store office very promptly for immediate use .
A microwave typically uses a high-octane capacitor, which, as the name suggests, operates at a a lot higher electric potential than capacitors in early electrical appliances .
Because they store electricity, capacitors are very dangerous. even if the microwave is unplugged from its ability provision, a capacitor can still cause severe electrocution injuries. so, be certain to safely discharge the power before doing anything or hire a qualify professional to conduct the haunt for you .
Why it fails: There are several reasons a high-octane capacitor in your microwave may short out and blow your microwave ’ s fuse .
If the microwave is calm new, the capacitor itself may be faulty. physical damage can besides cause the lapp, such as if the microwave has suffered a solid impact that damaged the capacitor .
In older microwaves, the capacitor may have simply worn out after many years of continue use .
When you press Start on your microwave, the high-octane capacitor is supposed to start working. That ’ s not possible if it ’ randomness shorted out, which is why it causes the microwave ’ mho blend to blow .
How to fix: Again, please be mindful that replacing a microwave ’ s high-voltage capacitor is very dangerous, as the capacitor holds an electrical charge even when you disconnect the baron add .

It is critical that the capacitor be discharged safely before working on any internal part of the microwave .
Suppose you hire person to replace the capacitor for you. In that case, they ’ ll begin by removing any panels on the microwave to entree the components inside .
They will then discharge the capacitor before unscrewing the mount that holds it in place. After disconnecting the electrical connectors, a new capacitor goes in .
The steps are reversed ; the electric connectors are reconnected, and the climb is screwed back in place .

Microwave Fuse Blows When Opening Door

In some cases, you may find that your microwave fuse blows precisely while you ’ re opening the appliance ’ second door. That ’ s a tell-tale sign of the zodiac that the door switch may have something to do with it .

Stuck Or Faulty Door Switch

What it is: The door switch that you find on a microwave international relations and security network ’ t the same as those on other appliances. Microwave switches serve respective purposes, each of them fabulously crucial to the safe operation of the appliance .
first, the door switch ensures that the microwave lone functions when the door is closed. That prevents anyone from being exposed to any dangerous microwaves when they ’ rhenium near the appliance .

Besides that, the door switch besides delivers might to electric components in the microwave, which heat up the food that you ’ ve placed inside the appliance .
Why it fails: As with many other microwave components, there are several reasons why the doorway interchange may fail. For starters, the door switch over may have barely gotten stuck .
Remember : switches open to allow world power to flow through the racing circuit, and they besides close to stop power from flowing through .
A door switch that gets stuck will fail to do what it ’ s supposed to do, leading to a fuse being blown when the doorway is opened .
The same may besides happen with a faulty or worn out doorway switch. A switch in this condition will not be able to do what it ’ s supposed to do, leading to a blend blow as a condom quantify to protect the appliance and its users .
last, a problem with the microwave door trade may besides happen if you ’ ve precisely fixed or replaced them .
If that ’ s the case, you or the technician may have unintentionally wired the switches incorrectly, causing them to malfunction whenever you open the microwave door .
How to fix: Microwave door switches are reasonably square to replace. however, microwaves are hush quite dangerous because they rely on high-voltage capacitors, as mentioned earlier .

so, if you or a technician removes the microwave ’ south panels to gain access to its components, bear in thinker that there is a eminent hazard of injury from electrocution.

It ’ s constantly best to refer to the microwave ’ s education manual to understand the inner layout of the appliance. That way, you ’ ll know what to look for once you ’ ve gained entree to the components inside .
Replacing the microwave doorway trade will normally involve removing a presence panel .
You may need to unscrew the caparison that holds the doorway switch in place and remove its electric connectors .
once the fresh switch has been put in, the connectors must go in the right manner, or else it will cause another blow fuse .
To ensure that you install the substitute switch and reattach the electrical connectors correctly, here ’ s a utilitarian tip off .
Take a photograph of the defective door switch over and its connectors before removing it .
By doing that, you ’ ll have a video that you can use as a reference book to ensure that you install the substitute correctly, equitable the like way as earlier .

Microwave Fuse Blows When Closing Door

Suppose your microwave fuse blows when you ’ re closing the doorway alternatively of opening it .
If that ’ s the case, then the cause is the same : you may have a cling or defective doorway trade .
You see, whether you ’ re opening or closing the microwave door, the component that reacts to that action is the microwave doorway switch. sol, that is most likely the cause of the trouble .

How Many Fuses Are In A Microwave?

Microwaves typically have several fuses inside, and they besides tend to be of unlike types .
Depending on the induce and model of your particular microwave, you may find fuses placed on exceed, behind, or tied by the side parts of the unit .
The best way to identify the quantity and locations of the fuses is to refer to your exploiter manual and any technical documents related to the model you have .
typically, these documents will map out the entire electrical circumference of the microwave, so you know where to find each fuse .
Microwaves use two types of fuses : ceramic and glass fuses. They ’ ra sacrificial components that are meant to get destroyed as a direction of cutting the tour to protect the appliance and its users .
Some microwave fuses called ‘ thermal fuses ’ are triggered by estrus. indeed, if the microwave overheats, the blend will blow and shut the power off to the microwave .
other fuses are triggered by excessive electricity flow through the circuit. A short circuit, for example, will cause that fuse to blow .

How To Test Microwave Thermal Fuse

Remember : a thermal fuse will blow if the microwave overheats. If you ’ d like to see if the fuse is silent working, you ’ ll need a multimeter to measure for continuity in that fuse .

startle by making sure that the multimeter is calibrated and set it to the lowest ohm rate, regardless of whether it ’ s a digital or analogue multimeter .
Remove the blend from the microwave and locate one of the multimeter ’ second probes on each terminal of the fuse .
If the meter reading shows no resistance, that means the fuse has continuity ( i.e. it still works ) .
But if the meter shows that there is no continuity, that means the thermal fuse has blown. You ’ ll want to find an allow surrogate for that thermal fuse .

Can I Use Any 20 Amp Fuse For My Microwave?

No, you can not simply use any 20 Amp fuse to replace a blow fuse inside your microwave. The key hera is to pay attention to the type of 20 Amp fuse that needs replace .
For the microwave you need to use 20A SLOW BLOW Fuse, not Fast Blow.

For model, you can use a ceramic 20 Amp fuse to replace a glass one, but NOT vice-versa .
If you ’ rhenium uncertain, it ’ south constantly best to play it safe. In this casing, that means referring to the user manual for your microwave or contacting the manufacturer .
By using the specific type of fuse that the manufacturer recommends, you ’ ll avoid any doubt about whether or not the fuse is dependable to use for your microwave .