How Does a Convection Microwave Oven Work?

How the Microwave Oven Works

Microwaves work by creating an electromagnetic field in the cooking chamber. This field agitates water molecules in the food, causing them to vibrate quickly and generate heat. This heat is then transferred to other parts of the food, ensuring even cooking. Microwaves cook quickly and efficiently because microwave energy heats only the food, not the whole oven cavity.

Four vital components create the electromagnetic microwave field inside the cooking chamber:

• Magnetron: This electron tube is the microwave’s power source, generating the high-energy electrons that cook your food. The magnetron produces microwaves by channeling electrical energy into a heated filament. This creates a flow of electrons that transmits microwaves into the microwave cavity. The microwaves bounce around through the metal interior cavity of the oven and are absorbed by the food. The microwaves agitate water molecules in the food, causing them to vibrate quickly and generate heat. This heat is then transferred to other parts of the food, ensuring efficient and even cooking.
• High-voltage transformer: This component supplies the high-energy electrical power needed by the magnetron to produce the stream of electrons.
• High-voltage capacitor: The microwave's capacitor works with a diode to convert the alternating current power output of the transformer to direct current (DC), increasing the voltage to nearly 5,000 volts. This additional voltage is necessary to power the microwave's magnetron.
• Wave guide: The wave guide directs the microwaves from the magnetron into the microwave oven cavity.

Although heat is produced directly in the food by agitating water molecules, microwave ovens don’t cook food from the inside out as many think. When thick foods are cooked, the outer layers are heated and cooked primarily by microwaves while the inside of thick food items is cooked mainly by the conduction of heat from the hot outer layers.

Glass, paper, ceramic, or plastic containers must be used in microwave cooking because microwaves pass through these materials. Although such containers cannot be heated by microwaves, they can become hot from the heat of the food cooking inside them. Generally, metal pans or aluminum foil should not be used in a microwave oven, as the microwaves are reflected off these materials causing the food to cook unevenly and possibly damaging the oven cavity.

If you accidently use foil or metal containers inside the microwave, schedule microwave repair service to have a technician examine the appliance and make sure that it’s safe to continue using.

How the Convection Oven Works

A convection oven uses a fan and heating element to circulate hot air throughout the oven cavity to heat food. Circulating the air around the food promotes even cooking. Although not as fast as microwave cooking, convection cooking does heat items faster than a conventional oven without the fan. An air fryer is a type of convection oven that uses a more powerful fan than the convection oven.

The fan removes moisture from the oven cavity during baking, which helps foods get crisp – something a microwave won’t do. This results in baked goods with crispy crusts and tender insides. It also creates crispy skins on meats.

How the Convection Microwave Oven Combines the Methods

Having the best of both worlds is always better. Although convection microwave has multiple cooking modes so you can use either method on its own, cooking with both methods at once will cook food faster and crispier. While the microwave function quickly heats the food by agitating water molecules using high-energy electrons, the convection element and fan work together to heat the outer layers of the food and create a crispy crust that helps the food retain moisture and stay tender and juicy inside.

Here are distinct advantages of using a convection microwave oven:

• Faster cook times: Items cook faster because the convection element, fan and microwave system heat the food simultaneously in different ways.
• Even cooking: The fan circulates hot air to cook food evenly while the microwaves also do the same.
• Moist food: Convection cooking helps food retain moisture by creating an outer crust.
• Better flavor: Convection cooking improves the flavor of food by browning the outer layers and creating crispy skins on meat.
• Uses less energy: Because they cook faster and more efficiently, convection microwaves use less energy than a traditional oven.

Maintaining a Convection Microwave Oven

Follow the instructions in the owner’s manual for your convection microwave oven for maintenance and cleaning. Keep the inside of the oven cavity clean and free of splatters. Splatters can cause arc marks inside the cavity. When you see small arc marks inside the cavity, follow the tips in this video to repair the damage:

As noted in the video, when you see large arc marks or damage in the microwave oven cavity, schedule microwave repair to have a service technician visit your home and fix the damage.

In addition to keeping the oven cavity of your microwave clean, schedule yearly professional microwave maintenance to have a Sears Home Services technician visit your home and check all microwave functions, make any necessary adjustments and perform professional cleaning to keep your appliance in top shape and lasting longer.