What To Do if You Accidentally Run the Microwave Empty? (Explained)

Categorized as Microwave Repair and Troubleshooting
Accidentally Run the Microwave Empty

You’re standing in front of the microwave, distracted and not paying attention, when you hit the start button without actually putting anything inside. We’ve all had that moment of fear and dread when we realize what has just happened—you ran your microwave empty.

But what exactly will happen if you do this? Will your microwave explode? Or is running a microwave empty no big deal at all? Let’s take a look at what could happen if you accidentally run the microwave empty.

Some Possible Consequences of Running a Microwave Empty

The Magnetron Could be Damaged

The magnetron is a tube inside your microwave that produces microwaves to heat up food. If you run an empty microwave, then these microwaves have nothing to bounce off of, so they will end up bouncing around inside the chamber of your microwave until they find something to interact with—namely, the magnetron itself. This can cause damage to the magnetron over time and will eventually require repairs or even replacement of the entire unit.

Possible Risk of Fire

In extreme cases, running an empty microwave can potentially cause fires. This is because if you run the microwave empty for too long, the microwave can be overheated to the point where it sparks and causes a fire. While this is extremely rare, it’s still possible and should be avoided if at all possible.

Possible Damage to Electrical Components

Even if no fire results from running an empty microwave, there are still other risks involved with doing this repeatedly. The repeated exposure of electrical components within your appliance such as capacitors and relays can wear them out over time leading them to fail prematurely and potentially requiring repairs or replacement of parts within your appliance.

How Long Can You Run The Microwave Oven Empty

Depending on the type of microwave, this threshold may vary between a few seconds up to five minutes. For most microwaves, running it empty for longer than five minutes. After this amount of time has passed, the internal components can overheat and suffer permanent damage. Some microwaves may even shut off automatically after a few seconds to prevent overheating.

What To Do After Accidentally Running the Microwave Empty?

The first thing you should do after running an empty microwave is to test your microwave. If it is still turning on and working properly, then you probably won’t need any further action.

To test your microwave, put a cup of water inside and heat it up for one minute. If the water gets hot then your microwave is probably still working properly.

If your microwave isn’t turning on or is making strange noises when you try to use it, then you should contact a professional repair technician who can diagnose any potential issues with your appliance.

Other Microwave Safety Tips That You Should Follow

1. Avoid Metal and Paper Containers

The safety rule when using a microwave oven is to avoid metal and paper containers. Metal can create sparks that may cause fires, while paper or cardboard can start burning if it gets too hot.

To avoid potentially hazardous situations, only use plastic, glass, ceramic and other microwave-safe containers for your meals.

2. Do Not Heat Flammable Food or Beverage

Foods or beverages that are flammable—such as alcohol-based liquids—should never be heated in a microwave oven. Microwave ovens generate a lot of heat and could potentially ignite the flammable material.

3. Place Your Microwave Away From Other Heating Sources

To prevent overheating, place your microwave away from any other heating sources such as the oven or stove. This will help to ensure that your appliance does not become too hot and cause any damage.

4. Don’t Use Microwave with Door Open

Never use a microwave with its door open. This could cause the microwaves to escape and potentially damage other components in your kitchen or home. To avoid any potential issues, always make sure to close your microwave door before turning it on.

5. Don’t Cover The Microwave Vent When It’s On

If you are microwaving food, never cover the vent with a towel or any other material. This can cause the appliance to overheat and possibly start a fire. Always make sure to leave the vent uncovered when using your microwave oven.

6. Turn Your Microwave Right Away If You Smell Something Burning

If you ever smell something burning while using your microwave, turn it off right away. This could indicate that the appliance is overheating. Wait until the appliance has cooled down completely before attempting to use it again.

7. Clean The Microwave Regularly

Cleaning your microwave regularly is also important to ensure that it is functioning properly. You should at least wipe down the inside of your microwave with a damp cloth three to four few weeks. This will help to remove any food particles that could potentially cause problems.

8. Unplug The Microwave When Not In Use

When not in use, make sure to unplug your microwave from the power source. This will help to prevent any potential fires or hazards while the appliance is not in use. Additionally, always unplug your microwave when cleaning it to avoid electric shocks.

9. Use Surge Protectors

If your microwave is connected to an outlet, make sure to use a surge protector. Surge protectors will help to protect your appliance from power surges and other electrical problems. They also offer an added layer of safety in the event of a power outage or blackout.

Also read: 11 Microwave Oven Safety Guidelines to Follow


As you can see, it is best not to run an empty microwave since it carries some potential risks including possible damage to its internal components as well as potential fire hazards in some cases.

That being said, one accidental slip-up probably won’t result in any major issues so don’t panic! Just make sure that when you do use your trusty kitchen friend next time make sure there’s something in there waiting for its turn in the spotlight before hitting that Start button!

By Rosie Elliott

I’m Rosie. I’m a professional chef with experience in Western, Mediterranean, and Italian cuisine. I’ve been cooking for over 15 years, and I have two daughters that keep me busy!