Whirlpool Microwave Not Heating? Here’s How to Fix It Fast

Have you ever put your food in the microwave, pressed start, and then realized it’s not heating at all? It’s super frustrating, especially when you’re hungry and need your meal warm quickly. I faced the same problem with my Whirlpool microwave, but after some checking and simple fixes, I got it working again. In this article, I will guide you step-by-step on how to find out why your Whirlpool microwave is not heating and how to fix it easily.

Check the Power Supply and Door Switch

The first thing you need to do when your Whirlpool microwave is not heating is to make sure it is getting power. Sometimes, the microwave may be plugged in, but the outlet might not work or the plug might be loose. Try plugging another appliance into the same outlet to see if it works. If the outlet is fine, then check if the microwave’s power cord is properly connected without damage.

Another important part to check is the door switch. Microwaves are designed not to work if the door isn’t properly closed. The door switch tells the microwave when it is safe to run. If this switch is broken or faulty, the microwave will not heat. You can test the door switch with a simple tool called a multimeter to check if it works. If the switch is broken, you will need to replace it.

If you are not comfortable using a multimeter, you can try this: close the microwave door firmly and listen for a clicking sound. That click means the door switch is working. No click means it might be broken.

• Check if the power outlet works by testing with another device
• Ensure the microwave plug is secure and the cord is not damaged
• Listen for the door switch click when closing the microwave door
• Test the door switch with a multimeter if possible
• Replace the door switch if it is faulty

Look Into the Magnetron for Damage

The magnetron is the main part of your microwave that creates the heat to cook your food. If the microwave turns on but does not heat, the magnetron might be the problem. Sometimes, the magnetron can burn out or get damaged over time.

You can check if the magnetron is bad by listening when the microwave runs. A working magnetron usually makes a humming sound. If you hear nothing or a strange buzzing, it might mean the magnetron is broken.

Another sign of a bad magnetron is a burning smell during operation. This smell shows the magnetron is overheating or damaged inside. If you suspect the magnetron, it is best to get it checked by a professional or replace it yourself if you feel confident. Remember, the magnetron works with high voltage, so safety is very important.

• Listen for humming sounds when the microwave is on
• Notice any strange buzzing or no sound at all
• Smell for burning odors when using the microwave
• Get a professional to check or replace the magnetron safely
• Avoid opening the microwave if you are not experienced

Inspect the High Voltage Diode and Capacitor

The high voltage diode and capacitor are parts that help the magnetron get the power it needs to produce heat. If either one of these parts fails, your microwave won’t heat even though it turns on.

The diode changes the electricity from AC to DC, which the magnetron needs. If the diode is bad, the magnetron will not get the power and your food won’t heat. You can test the diode with a multimeter for continuity, but if you see signs like burning or the microwave stops heating suddenly, the diode could be the cause.

The capacitor stores electrical energy and works with the diode. A bad capacitor may cause the microwave to stop heating or cause other electrical problems inside.

Replacing these parts is a bit technical and requires safety care because they hold electric charge even when unplugged. If you are not sure, call a repair expert.

• Check for burning smells or visible damage near diode or capacitor
• Use a multimeter to test the diode for continuity if you can
• Know that a faulty diode or capacitor can stop the microwave from heating
• Get expert help to replace high voltage parts safely
• Never touch capacitor without discharging it first for safety

Clean the Waveguide Cover and Inside Microwave

Sometimes, the problem might not be electrical but simple cleaning. The waveguide cover is a small panel inside the microwave that helps direct the microwave energy evenly. If this cover is dirty, greasy, or damaged, it can cause the microwave to stop heating properly.

Check the inside of your Whirlpool microwave for food splashes, grease, or dirt on the waveguide cover. Clean it gently with a damp cloth and mild soap. Don’t use too much water or harsh chemicals. If the waveguide cover looks burned or damaged, replace it.

Also, keeping the inside of your microwave clean helps it work better. Food particles can block the microwave energy and stop heating. Clean the interior regularly.

• Inspect the waveguide cover for dirt, grease, or damage
• Clean with a damp cloth and mild soap carefully
• Replace the waveguide cover if it is burned or damaged
• Wipe down the microwave interior regularly to prevent buildup
• Clean microwave parts help the heating work better

Reset the Microwave Control Board

The control board is like the brain of your microwave. Sometimes, it can get stuck or glitch and cause the microwave to stop heating even if everything else is fine.

Try resetting your Whirlpool microwave by unplugging it from the power outlet for about 5 to 10 minutes. This lets the control board reset itself. After waiting, plug it back in and try heating something again.

If the microwave still does not heat after a reset, the control board might be faulty. Signs of a bad control board include buttons not working, strange error codes, or the microwave turning on but not heating. In this case, replacing the control board may be necessary.

• Unplug the microwave for 5-10 minutes to reset the control board
• Test if the microwave heats after the reset
• Look for signs like unresponsive buttons or error codes
• Replace the control board if it is not working properly
• Resetting can fix small glitches without repair

Test the Thermal Fuse and Thermoprotector

Safety parts like the thermal fuse and thermoprotector stop the microwave from overheating and getting damaged. If either one blows or breaks, it will stop the microwave from heating to protect it.

You can test the thermal fuse with a multimeter to see if it has continuity. If the fuse is broken, you will need to replace it. The thermoprotector works similarly and can also be tested.

Sometimes these parts blow because the microwave overheated or worked too long without breaks. If these keep breaking, check the cooling fan or vents to make sure air flows properly inside the microwave.

• Test thermal fuse and thermoprotector with a multimeter for continuity
• Replace blown thermal fuse or broken thermoprotector
• Check cooling fan and vents if fuses blow repeatedly
• Safety parts protect microwave from overheating
• Replace safety parts promptly to get microwave heating again

Call a Professional if You Can’t Fix It Yourself

If you have checked all the above parts and your Whirlpool microwave is still not heating, it might be time to call a professional repair technician. Microwaves contain high voltage parts that can be dangerous if you don’t know what you are doing.

A professional can quickly find the exact problem and fix it safely. Sometimes, the repair cost might be close to buying a new microwave, so they can also advise if it’s better to replace.

Remember, microwaves are complicated machines. Trying to fix something without proper tools or knowledge can be risky. If in doubt, ask for help.

• Call a professional repair technician for safety and accurate fix
• Professional can test all parts and find the problem fast
• Consider repair cost vs buying a new microwave
• Avoid dangerous repairs without experience
• Get advice on the best option for your microwave

Final Thoughts

A Whirlpool microwave not heating is a common problem but one you can often fix at home. Checking the power, door switch, magnetron, and other key parts carefully will help you find the cause. Cleaning and resetting the microwave sometimes solve the issue without costly repairs. Always remember safety first, especially when dealing with high voltage parts. If the problem seems too big, calling a professional is the best way to go. With these easy steps, your microwave will be heating your meals again in no time.

Frequently Asked Questions (FAQs)

Is it normal for a microwave to hum when heating?

Yes, it is normal for a microwave to hum when heating because the magnetron produces microwave energy, which creates a humming sound. This sound shows the microwave is working properly to heat your food. If you don’t hear the hum, the magnetron or high voltage parts might be damaged. Always listen to your microwave as a sign it is working well.

Can a dirty waveguide cover stop my microwave from heating?

Yes, a dirty or damaged waveguide cover can stop your microwave from heating properly. The waveguide directs the microwave energy inside the oven. If it’s blocked by grease, food, or burnt spots, the microwave can’t heat food evenly or at all. Cleaning or replacing the waveguide cover usually fixes this problem.

Do I need a professional to replace a magnetron?

Yes, replacing a magnetron is not easy and can be dangerous because it works with high voltage electricity. If you don’t have experience or proper tools, it is better to call a professional. A professional will safely remove the old magnetron and install the new one without risk to you.

Is unplugging the microwave a good way to fix heating problems?

Unplugging the microwave for a few minutes is a good way to reset the control board and fix small glitches. Sometimes, the microwave just needs a reset to start heating again. If unplugging does not help, the problem is likely a faulty part that needs repair or replacement.

Can a bad door switch cause the microwave not to heat?

Yes, a bad door switch will stop the microwave from heating because the microwave thinks the door is open and won’t run the magnetron for safety. Checking and replacing a broken door switch is often an easy fix for heating problems.

Do I need to clean the microwave inside regularly?

Yes, cleaning the microwave inside regularly helps keep it working well. Food and grease buildup can block microwave energy and cause uneven heating or no heating. Wiping the microwave interior and waveguide cover gently with a cloth keeps your microwave healthy.

Is the thermal fuse easy to test and replace?

Testing the thermal fuse is easy if you have a multimeter. You check for continuity to see if it is working. Replacing it is also straightforward but requires unplugging and opening the microwave. If you don’t know how to handle electrical parts safely, ask a professional to do it.

Can I keep using the microwave if it smells burning?

No, if your microwave smells burning, it could be dangerous. The smell usually means a part inside is overheating or damaged. Stop using the microwave immediately and check for damaged parts or call a professional to avoid fire risk.