What Makes Your Microwave Noisy (The Main Culprits)

If you have a particularly old microwave, keeping up with the various noises it can produce can be a challenge. You might find yourself hearing new and interesting sounds every other day. From humming and buzzing to vibrating and rattling, there’s nothing I haven’t heard from my old microwave.

And sure, while some of these sounds are a sign that something is wrong with the appliance, others are a normal part of the process. So let’s talk about that process for a second.

How Do Microwave Ovens Even Work?

Well, there is usually a component in the back of the appliance called the magnetron. This tube is responsible for creating the energy that is then directed toward the food you’re heating by the waveguide, an angled part of the inner wall. These waves warm the food from the inside rather than the outside, as is the case with regular ovens.

Obviously, microwaves have other parts in them, but these are the main ones responsible for heating your food. So what’s so noisy about all of this? Better yet, how can the answer to that question help you avoid purchasing a noisy microwave?

Why Your Microwave Is Making Noise

Many people wrongfully assume that the magnetron is the main noisemaker here. To be fair, the parts that generate the energy are usually the noisy bits of any contraption. In this case, though, it’s likely that the exhaust fan, which is meant to regulate the temperature of the microwave, is behind the whooshing and humming.

The only way the magnetron would be making noise is if it were loosely attached and vibrating against the body of the appliance. But there are other things to worry about besides the standard humming sounds you might hear while your food is heating up.

Just like your phone charger, these appliances have your standard electrical noisemakers — diodes, capacitors, and transformers. If this trinity starts misbehaving, expect to hear a faint buzzing sound even when the appliance isn’t on. That, as well as grinding or clanking, is a sure sign that you’ll soon need to get rid of your old microwave and get a new one.

Now, I also want to address the elephant in the room. Most of the time, the loudest sound any microwave oven can produce is whatever atrocious alarm goes off when your food is ready. It can be a single “ding” sound, continuous beeping, or something else altogether.

Either way, it’s usually incredibly obnoxious. With that in mind, your main goal should be to find a quiet microwave that won’t sound off like a bomb when it’s done heating your food.

Related: Can You Put a Microwave in a Cupboard?