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How Do Diffusers Make Steam? A Comprehensive Guide for Beginners

How Do Diffusers Make Steam? A Comprehensive Guide for Beginners

Did you know you can use a diffuser at home to relax and calm? The amounts of diffusers you buy depend on the size of the room. For instance, a room that’s 1000 sq. ft. needs at least two diffusers; that way, steam distribution is even.

However, the question that arises as you use one is how do diffusers make steam?

Diffusers transform your home into an oasis of tranquility by dispersing essential oil-infused steam. They provide the right amount of vapor and humidity to fill the entire room. But it’s pretty okay to get curious about how the small device functions.

How is it possible for it to produce steam or vapor, or mist? The best way to understand this is to look into the different types of diffusers in the market today.

Types of Diffusers

As you find out how diffusers make steam, it’s good to note the different types available today. There are four types of diffusers that you can use at home. These include:

  1. Evaporative Diffusers
  2. Heat Diffuser
  3. Ultra Sonic Diffuser
  4. Nebulizing Diffuser

1. What is an Evaporative Diffuser?

An evaporative diffuser is also known as a fan diffuser. There are two types of evaporative diffusers in the market.

One uses the air current in a room to spread vapor. Another requires a fan to function similarly.

However, these are some of the simplest diffusers you can buy for your home. They have a simple mechanism that suits first-time diffuser users.

When you have an air current evaporative diffuser, it relies on the air current in your room. Once you switch it on, the air current assists the device to spread vapor in the room, depending on its size. You need to pick out the right size for the room.

On the other hand, an evaporative fan diffuser such as Stadler Form 0-021 OSKAR Evaporative Diffuser comes with an in-built fan inside. The fan pushes the steam out and spreads it across the room. You can use it in a bigger room but still get ample vapor distribution.

How Does an Evaporative Diffuser Work?

What happens inside every evaporative diffuser? These are essential questions to help you understand the device better. Once you do, you can enjoy using it at home much more.

An evaporative diffuser can either come with a fan or not. But, the primary mechanism is the same in both devices. Every evaporative diffuser has a soaking pad inside. The pad requires essential oils to function correctly.

How Does an Evaporative Diffuser Work

Once you get the device, soak the pad with a couple of drops of your favorite essential oil or blend. After that, you turn on the device and wait for the aroma. Once the device is on, the liquid on the pad starts evaporating.

When evaporation begins, vapor distribution is next, either using an air current in the room or a fan in the device. Simpler devices that don’t have a fan use the air current to spread the vapor in the room. However, even those with fans do a proper job.


  • The evaporative diffuser is quiet. You won’t need to worry about noise disturbing your sleep.
  • You can choose to have a fan or not.
  • The device is affordable.
  • An evaporative diffuser is simple to use and therefore beginner-friendly.
  • No water is needed for the device to function correctly.
  • Most are small and portable.


  • You end up using lots of oil which isn’t economical.

2. What is a Heat Diffuser?

Before delving deeper into that, it’s vital first to understand what a heat diffuser is.

A heat diffuser such as  NJCharms Ceramic Tealight Holder Essential Oil Burner relies on heat to spread essential oil particles in the room. Without a source of heat, you can’t use the device successfully. There are two ways of using a heat diffuser.

First, you can use pure essential oil without needing to mix it with water. Or, you can mix the oil in water inside the heat diffuser.

Typically, the critical factor for this device is the amount of heat it uses. The good news is it’s among the lowest energy consumers you can have in your home. That lowers your utility bills as you enjoy unique fragrances.

Also, it’s among the most affordable essential oil diffusers on the market.

How Does a Heat Diffuser Work?

Once you purchase a heat diffuser, you need to place drops of essential oils in it. You can use the oil alone or mix it in water. Just be sure to check out the instructions on the device before you pick one.

After placing some oil in it, the heat warms it up. The amount of heat must be enough to release vapor. However, it mustn’t tamper with the molecular structure of the oil. When you have vapor, the air current can distribute it in your room.

How Does a Heat Diffuser Work

Remember to pick the suitable heat diffuser for your home in terms of size. Using a small capacity heat diffuser in a big room won’t give you the results you desire. Also, keep the heat low to keep releasing steam.

Now you have a better understanding of how heat diffusers make it.


  • Using heat is an economical way of using the diffuser.
  • It consumes less energy, meaning you won’t need to worry about high utility bills.
  • It produces little to no noise while on. It means you can keep it on all night.
  • You can choose to use the oil alone or add a few drops to water.
  • Vapor distribution occurs as a result of air currents in the room.


  • Too much heat ends up impacting the essential oil molecules. When the molecules are affected, the aroma isn’t much significant.

3. What is an Ultrasonic Diffuser?

Another favorite diffuser you can use is the ultrasonic diffuser.

Before answering that crucial question, it’s better to start with the basics. An ultrasonic diffuser is among the most popular in the world. Almost half the homes with diffusers opt to use the ultrasonic models.

Not only are they stylish, but they are pretty economical. For instance, you can use a small amount of essential oil on the device and end up with phenomenal results. However, most are electric, meaning you need some source of electricity.

Additionally, ultrasonic diffusers have a water reservoir inside. You need to fill it with water and add the essential oil to function the right way.

The good news is you won’t need a source of heat to release the steam from the device. A good example is the ASAKUKI 500ml Premium Essential Oil Diffuser.

How Does an Ultrasonic Diffuser Work?

Though these devices use electricity, they don’t rely on heat to release steam.

An ultrasonic diffuser requires vibrations to release steam. After you fill the reservoir and add the oil, plug it and turn it on. Ensure you have a plug near the device.

How Does an Ultrasonic Diffuser Work

When the diffuser is on, it starts vibrating. The vibrations impact the essential oil molecules in the water mixture. The impact on the molecules turns them into vapor. Next, the device releases the vapor as steam which spreads across the room.


  • Most ultrasonic diffusers are classy and blend well with house décor.
  • The device produces no noise when you switch it on.
  • You only need a few drops of oil at a time.
  • With varying water reservoirs, there’s a diffuser for every room size.
  • You can use LED lights to create ambiance in the room.


  • Most of the steam is water. Only a tiny amount contains the essential oil.
  • Insufficient air current in the room results in uneven steam distribution

4. What is a Nebulizing Diffuser?

It’s safe to say that a nebulizing diffuser shares certain similarities to an ultrasonic device. However, you need to know how to distinguish the two when you want to purchase one.

What is a Nebulizing Diffuser

A nebulizing diffuser releases steam but doesn’t require water to do so. All it requires is the essential oil, and you are good to go. Inside the device, you can find a small tank to fill with the essential oil or blend.

A good example is.

How Does a Nebulizing Diffuser Work?

A Scentcares Waterless Diffuser for Essential Oils uses an air pump to make steam. Once you fill the reservoir with essential oil, close it up.

After that, you need to activate the air pump. In most nebulizing devices, the air pump is right above a small tube after the oil tank. When you activate the air pump, it blows air into the nebulizing diffuser. The air current travels above the tube, resulting in a vacuum due to the rapid speed.

Once the vacuum forms, it attracts small particles from the essential oil in the reservoir. Next, the device releases these particles around it. With a good air current in the room, the particles start to travel all around. Since you’re not using water, you might need more essential oils.


  • You don’t need heat for the device to work.
  • Nebulizing diffusers don’t need water to distribute essential oils in a room.
  • Most devices are lightweight and easy to carry from one spot to another in a room.
  • The device delivers 100% pure essential oil vapor that’s not mixed with water.


  • The device is expensive to buy.
  • Since there’s no water in the reservoir, you end up using lots of essential oil.
  • Some nebulizing diffusers make lots of noise which can be pretty distracting.

Final Takeaway

The best way to understand how do diffusers make steam is by looking at the four types of diffusers and how they work.  The four types include evaporator, heat, ultrasonic, or nebulizing diffusers.

Each uses different mechanisms to release essential oil-infused steam in a room. They all have the same purpose but use different methods to make steam.