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Humidifier Buying Guide: Everything You Need to Know About Portable Humidifiers

Searching for a portable humidifier? Start here.

AJ Dellinger Contributor
AJ Dellinger is a contributor to CNET.
AJ Dellinger
5 min read
a humidifier

Portable humidifiers add moisture to smaller spaces -- and can easily be moved from room to room as needed.

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Have you ever noticed that the air starts to feel dryer during the winter months? It's not your imagination, it's actually happening. The colder air that accompanies the winter doesn't contain the same amount of moisture as the warm, summer air. Adding to this dry effect is the fact that running your heating system or furnace can remove additional moisture in the air, resulting in the air in your house becoming even drier. This can lead to dry, itchy and cracking skin, which is unpleasant and potentially harmful to your health.

Luckily, there's a tool that can help with this predicament. Humidifiers help to add moisture into the air. This can not only be good for your skin, but help make your home feel more comfortable through the cold winter months. So what's a humidifier, how does it work, and which kind is right for your home? Below, we'll walk you through the basics of humidifiers so you can purchase one with confidence.

Read more: Best Portable Humidifier for 2022

What are portable humidifiers?

There are several different kinds of humidifiers, including whole-home and portable models. For the purposes of this buying guide, we're going to focus on portable humidifiers. These are small but powerful devices that can be set up in basically any home. Most humidifiers operate simply, with a power source and tank for water. How they help to add humidity to the air depends on the type of humidifier that you purchase.

There are six types of portable humidifiers:

  • Cool mist: Ideal for warmer climates, cool mist humidifiers add moisture to the air without raising the temperature in the room. Cool mist humidifiers are the most common type of humidifier.
  • Warm mist: Best for colder climates, warm mist humidifiers don't just help to make the air more moist but also can add heat to the room.  
  • Dual-mist: Dual-mist humidifiers can provide either a cool mist or a warm mist, depending on which you prefer or is better for the conditions that you are living in.
  • Ultrasonic: Ultrasonic humidifiers use vibrating metallic diaphragms, which use vibrations to create water droplets and release them into the air to add moisture. They are quiet and use little energy, and can provide cool or warm mists.
  • Evaporative: Evaporative humidifiers use a fan to circulate humidity through a moist wick filter to release moisture into the air. They are the lowest-maintenance option but only produce cool mists. Most cool mist, warm mist and dual-mist humidifiers are evaporative.
  • Vaporizers: Vaporizers can alternate between warm mist or cool mist, but they utilize more energy than most and can be dangerous because of how warm they get.

How humidifiers work

While the function of a humidifier will vary depending on the type you decide on, the majority of humidifiers operate with a similar concept. A reservoir of water is slowly dispensed into a basin, where it is absorbed by a wicking filter. A fan blows air through the filter, which evaporates the water and helps to add moisture to the air. Most humidifiers are self-regulating, so as the humidity in the room increases, the amount of vapor produced decreases.

The benefits of humidifiers

There are a number of benefits to using a humidifier, from your personal health to the overall conditions of your home. Here are some of the primary benefits:

  • Reduce the risk of disease. Adding humidity to the air helps reduce dry air. Dry air can allow viruses and other bacteria to live longer, increasing your likelihood of becoming infected. Humidifiers help to add moisture to the air and reduce the risk of catching these airborne bacteria.
  • Improved breathability. Dry air can lead to sore throats, dry eyes and irritated airways. Adding moisture to the air makes it more breathable and is easier on your body.
  • Improved temperature control. Dry air can be difficult to manage and often does not hold heat as well, resulting in additional heating costs and even drier air as you try to warm up. Humidifiers add moisture to the air and make it easier to control the temperature.
  • Improved skin conditions. Dry air often results in dry skin that can become itchy, flaky and cracked. Moisture helps to combat these conditions.

Where to buy humidifiers

Portable humidifiers are a common household accessory. Because of this you can find them in many places that sell common home goods. Big box stores like Target, Walmart and even stores like Home Depot and Lowe's typically stock portable humidifiers. So, too, do pharmacy stores like Walgreens and CVS. You can also purchase portable humidifiers online from places like Amazon. They range in price from less than $20 to $200 or more

How to set up a humidifier

Most portable humidifiers are rather simple to set up. You will plug them in, fill the reservoir with water and allow it to disperse the moisture into the air. You'll want to read your humidifier manual to make sure that you are operating it correctly. While most humidifiers will run just fine with tap water, some require or operate better with distilled water. This also helps to prevent build up of any sort of mineral dust. If you are using a warm mist humidifier or a humidifier that gets hot during operation, make sure you keep it on a safe surface and out of the reach of animals or children who may touch it.

Watch this: Easy Ways to Lower Your Utility Bills and Save Money

How to maintain and clean a humidifier

Cleaning a humidifier is easy and essential, as you don't want to distill bacteria or dirt into the air. Each humidifier will be a little different, but in general, the cleaning process will be similar no matter what.

Turn off your humidifier and make sure the reservoir and basin are empty. Fill the tank with undiluted white vinegar. Allow it to stand for 15 to 20 minutes, then empty it and scrub the area to remove any mineral deposits. Rinse thoroughly, let it dry, then put it back together so you can run it again.

The best practice for keeping your humidifier clean is to give it a cleaning once a week. This will make sure that any build up that does occur is kept to a minimum and addressed quickly.

Two final thoughts

If your humidifier suffers any damage or stops functioning, you can check the warranty and replace it. Most humidifiers come with a one-year warranty and you may be able to replace it through the retailer where you initially purchased it. Otherwise, you will have to contact the manufacturer. 

Portable humidifiers are simple and effective tools for keeping the air in your home moist, even through the dry winter months. This helps to improve air quality, keep you healthy and keep heating costs down. They are easy to maintain and provide great benefits with minimal cleaning. Consider the different types of portable humidifiers available and go from there -- there's bound to be an option to suit your needs.