(Last Updated On: March 28, 2023)

 Product Review: Coway AirMega 400

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By Bianca Herron

12 min read

Coway is passionate about helping people create a path to cleaner, healthier indoor air. Suffice it to say, the company’s products are expertly designed, include several smart features and filters, and can meet anyone’s needs on a budget. Additionally, the award-winning company doesn’t sacrifice quality and provides a dedicated customer service team to help customers through every step of the process.

Whether you’re looking for an air purifier for asthma, allergies, smoke, or odors, Coway has an air purifier to meet your needs. Its Airmega product line, including the Airmega 400, features the Coway Max2 filter, a single filter featuring Activated Carbon and True HEPA components. No matter what your needs are, Coway offers a variety of quality indoor air solutions to help you and your loved ones breathe healthier, cleaner air.


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For more than three decades, Coway has been committed to helping people live healthier and breathe clean indoor air. Today, Coway has earned a reputation in the industry for manufacturing some of the best air purifiers, water purifiers, and bidet toilet seats on the market. Coway has become an award-winning company known for its design, innovation, and technology. Some of its awards include the CES Innovation Award, Good Design, Reddot, and the iF Design Award.

 Through its Coway Research & Development Center, the company develops and researches technologies that help people live healthier lives. The environmental technology research institute also operates as Coway’s environmental quality, design, and cosmetics institute. Since its launch, the Coway R&D Center has more than 8,000 patents related to water and air, over 5,000 intellectual property, 23 WQA-Certified Water Specialists (CWS), and collected more than 380 billion data points from over 40,000 households to test air quality.

If you’re looking for an air purifier that can expertly clean the air in a large room — including your bedroom, office, or living room — up to 1,560 square feet, the Coway AirMega 400 air purifier is an excellent choice. The smart air purifier is also energy-efficient and eliminates up to 99.97 percent of airborne particles as small as 0.3 microns. This includes pet dander, pollen, dust, and mold. 

Even better, the Airmega 400 also features the Coway Airmega Max2 filter, a single filter featuring Activated Carbon and True HEPA components, as well as a washable pre-filter that helps catch larger airborne particles. Additionally, the unit comes with a Smart Mode (three settings), Timer, Filter Light Change Indicators, and a five-year warranty. It also automatically adjusts to your environment based on the room’s air quality. 

The Coway Airmega 400 is easy to use and simple to operate, and affordably priced at just under $500. If you or a loved one suffers from allergies, asthma, dust, and other allergens, the Airmega 400 is a smart choice to help eliminate these harmful airborne pollutants.

The Coway Airmega 400 is an excellent choice if you or a family member has asthma, allergies, smoke, odors, and dust. With two color options, white and graphite/silver, the unit can easily fit in with any decor. It also runs quietly, meaning it won’t disturb anyone resting or interrupt your listening when watching your favorite T.V. show or program.

While it’s easy to open and unbox the Airmega 400, you may need help removing the unit from the box as it weighs nearly 25 pounds. Outside of that, you shouldn’t require any further assistance. After removing the unit from the box, place it in your designated area — works best in a room with the highest airborne pollutants — and plug it into a power outlet.

Before turning your new Coway Airmega 400 on, you must remove all wrapping of the unit, including the filters. Next, it’s equally important that you read the user manual not only to understand the features that come with your unit but so that you also know how to operate it. Additionally, when powered on, the unit is automatically set to Smart Mode. If you prefer a different mode, touch the sensor to choose from three different speeds.

You can expect to pay between $100 to $1000 for a good air purifier in today’s market. Coway falls in the mid-range price with its products. Coway offers an extensive product line and variety in air purifiers, which means there’s an air purifier to meet anyone’s needs as well as their budget. The Coway Airmega product line ranges from $189 to $749. If you cannot shell out the cash upfront, you can take advantage of easy monthly payment options during checkout on Coway’s website. All Coway air purifiers come with a 30-Day Back Money Guarantee, five-year limited warranty, and free shipping.

After reading dozens of online reviews, including Amazon, we found that most people who purchased the Coway Airmega 400 air purifier are satisfied and happy. Many customers expressed their appreciation for the unit’s ease of use, durability, quiet operation, and how it expertly eliminates harmful airborne particles. On the other hand, some customers also expressed that the unit is noisy, emits an odor, and issues with the unit itself.

Coway is committed to providing its loyal customers with exceptional customer service. If you are experiencing any problems with your air purifier or filter, Coway has an informational FAQ page helpful. You can also contact the company’s friendly customer service team via phone (800-285-0982) and email at [email protected]. Coway also encourages customers to utilize its Heart Service, a high-quality maintenance service provided by Coway Ladies.

Additionally, Coway provides its customers with free shipping on orders anywhere in the United States and Puerto Rico. Coway does not offer international shipping and does not ship to P.O. boxes, United States territories, or packaging forwarding services. All orders placed after close of business hours are processed and shipped the next business day. Moreover, Coway’s 30-Day Money Back Guarantee allows you to return any product, for free, that you’re not happy with.

Blueair Blue Pure 311 Customer Reviews:

We love it!

“We’ve owned the Airmega 400 for about two months. It sits in a room next to the kitchen and backyard sliding door. When strong kitchen odors are present, the Airmega turns into high gear automatically, and the light changes to red. I was opening a delivery package that was filthy and dusty about 10 feet away from the Airmega, and again it sensed the flying dust and kicked into high gear. Most of the time, it runs on the lowest setting and is super quiet. Very Quiet! We’ve noticed fewer dust and animal odors overall. Super easy to operate. It just operates itself, and it will let you know when to wash the large washable particle filter. So far, the HEPA is functioning at 100 percent efficiency. We love it! 

— Kristen D. via Amazon 

My lungs feel great!

“The River Fire has devastated our typically clean air in Paso Robles, CA. I’m super healthy, but my lungs could feel the stress of an AQI that was averaging between 390 and 412 (500 is the top). I did a lot of research and decided that this air purifier seemed like my best choice. Well, it kicked ass! It lit up red when I plugged it in (meaning bad air). It took maybe an hour to recycle the air and maintain a blue indicator light meaning good air. It’s running at the highest level because the exterior air remains hazardous. My lungs feel great, and no resulting allergies from the smoke drift. This unit kills! Note to the reviewer that said the unit smelled bad—perhaps you didn’t remove the plastic wrap around the HEPA filters? The air in my home is now totally purified. Thanks Coway.”

— Bonnie via Amazon

Today, indoor air quality is more important than ever. According to the Environmental Protection Agency, indoor air pollutants are two to five times higher than typical outdoor concentrations. Since Americans spend nearly 90 percent of their time indoors, you must take the necessary steps to ensure you and your loved ones are breathing clean, healthy air. The Coway Airmega 400 is an excellent solution. While the unit may be a bit pricier than some of its competitors, the many positive online reviews are a testament to its quality, ease of use, and, most importantly, its effectiveness at removing harmful airborne pollutants from the air.

Coway Air Purifier Products

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