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BACKNOV 19, 2025
How to Fix a Microwave That Is Not Heating
BACKNOV 19, 2025
Looking for more guidance? Take a look at our Repairs overview.
It’s a scenario we’ve all experienced. You place your leftovers in the microwave, set the timer, and press start. You hear the familiar hum, the turntable spins, and the light comes on. But when the timer beeps, you open the door to find your food is just as cold as when you put it in. A microwave that runs but doesn't heat is one of the most common—and frustrating—kitchen appliance issues.
Before you start pricing out new models or scheduling a costly repair, the good news is that the fix is often simpler than you think. Many causes of a non-heating microwave can be diagnosed and resolved with a few easy troubleshooting steps.
In this guide, we’ll walk you through the process of figuring out why your microwave isn’t heating up, just like we’re on the phone with you. We’ll start with the simplest checks and work our way through the potential culprits, helping you get your trusty appliance back to warming up your coffee and cooking your popcorn in no time.
A microwave is a complex piece of equipment, but the reasons it stops heating usually boil down to a handful of issues. Here are the most frequent causes:
Ready to play detective? Let's figure this out together.
We’ll start with the basics. The very first step is to determine if your microwave is getting any power at all.
Let's see if there are any signs of life.
If the answer to both of these questions is NO—the light is off and the display is blank—then you likely have a power issue. You can skip ahead to the section "What to Do When There’s No Power."
If the answer is YES—the light and display are working, but the microwave just isn't heating—then it's receiving power, and the problem lies elsewhere. Let’s move on to the next step.
If your microwave has power, the next place to look for answers is the control panel itself.
If you find an error code that points to a serious internal failure, or you can’t find information on it, it’s best to contact the manufacturer or a qualified appliance repair technician.
If there are no error codes, it's time to test the most common mechanical failure point: the door.
Your microwave has several safety switches inside the door latch mechanism. If even one of these isn't engaged, the microwave will run (turntable, fan, light) but the magnetron will not activate to produce heat.
If the water is hot, fantastic! The issue was likely a door that wasn't fully latched or a temporary glitch. If the water is still cold, the problem is likely internal, and you should proceed to the section on "When to Call a Professional."
If your initial check in Step 1 revealed a completely dead microwave (no light, no display), the problem is almost certainly electrical. Here’s how to trace it.
First, is your microwave a countertop model with a visible plug, or an over-the-range model that's built-in?
A microwave is a high-power appliance and can sometimes trip its circuit breaker, especially if other appliances on the same circuit are running.
If resetting the breaker restored power and your microwave is now heating, you've solved the problem! If the breaker trips again immediately, you may have a bigger electrical issue and should call an electrician. If the microwave still has no power or won't heat after the reset, it’s time to call in an expert.
While many microwave issues are simple fixes, some problems require an expert. According to Forbes, the average cost to repair a microwave is around $150, but it can range from $50 to $400 depending on the problem.
It's time to call an appliance repair technician if:
A Critical Safety Warning: Never attempt to disassemble your microwave to repair internal components yourself. Microwaves contain a high-voltage capacitor that can store a lethal electrical charge for hours or even days after being unplugged. This is a job strictly for trained professionals.
Dealing with a microwave that won't heat can disrupt your daily routine, but with a logical approach, you can often diagnose the problem yourself. By checking the power, inspecting the door, and resetting the breaker, you can solve the most common issues without spending a dime.
For those trickier problems, or for any home maintenance task that feels out of your league, help is just a tap away. Download the Casa app today! Our app provides easy-to-follow guides for hundreds of DIY home repairs and can connect you with vetted, reliable professionals when you need one. Take control of your home maintenance with Casa.
