This smart air purifier is quieter than a computer and turns on automatically when it senses polluted air in my home

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An air purifier of high quality should be able to filter out irritants from your home or room while running quietly.

The Coway Airmega 400 Smart Air Purifier is my favorite because it automatically adjusts the fan speed according to the air pollution level.

You can barely hear the motor running on the lowest setting. It looks great in my dining area.

It is a good idea to find a way to improve indoor air quality if your home is clogged with dust, pollen and pet hair. A high-quality purifier will help you do some of the cleaning and vacuuming that can improve your indoor environment.

The Coway Airmega 400 Smart Air purifier has been great. It's a brand new model by one of the most respected names in the industry.

Design and specifications

In just 15 minutes, the Coway Airmega400 cleans air in a room measuring 760 square feet. Coway

The Airmega 400 comes in two colors: graphite/silver and white. The graphite model was easy to match my darker dining room. It measures 23 inches in height and 15 inches deep. However, it doesn't take up too much space.

It is 25 pounds heavy so it can be difficult to transport around in order to purify the air inside your home. It does have handles on either side for easy transport if you need to.

These are other important details:

Coverage: 24,960 cubic feet/hour. It can clean a room measuring 28 x 28 ft with a 8-foot ceiling, four times per hour.

24,960 cubic feet/hour It can clean the air in a room 28 feet by 28 feet with an 8-foot ceiling, four times per hour. Filters: Prefilter washable and Max2 filter set. This is a single filter with True HEPA and activated Carbon components.

: Prefilter washable and Max2 filter set. This is a single filter with True HEPA and activated Carbon components. Rated Voltage: 120 V 60 HZ

120 V 60 HZ Energy Star-certified. Power: 66 W

: 66W and Energy Star-certified. The timer can be set to automatically turn the purifier off after 1, 4, or 8 hours.

The setup process

The Airmega 400 setup was very simple. The process was simple: I took out the packaging and plugged it into a power socket. It took approximately 15 minutes to complete the entire process.

Before you turn on the Airmega, make sure that all plastic is removed from both Max2 filters. It is a simple task that made it easy to get used to the device. The user manual provides detailed instructions.

The unit is automatically set up to use Smart Mode when you turn it on. I'll explain more below. You can choose from three different air speeds. Simply run your finger along the touch sensor and choose the mode that interests you. Smart Mode is what I use most often.

What makes an air purifier stand out?

My experience with the Airmega 400 was that it did an excellent job clearing the air. It's also extremely quiet. The only way to know if the Airmega 400 has been set to low is to place your hand on the vent and feel the breeze. My sound meter measured 39 decibels from four feet away. This is quieter than a computer. The sound meter measured 55 decibels when the fan was turned up, which is still less than the average conversation.

It was only when I was cooking in the kitchen and my wife was smoking inside that I noticed it actually working. I also was lighting incense, but not simultaneously. The LED would change color from blue to red depending on the pollution detected by the purifier. This would cause the fan to speed up.

The Airmega 400 is Energy Star certified and has a Smart Mode. The fan will automatically stop when it is in Smart mode after 10 minutes of low levels of pollution. It will automatically turn on if it detects any pollutants in the air and it will restart until it reaches the level that indicates good air quality. This allows you to save money on your electric bill.

It is easy to clean and maintain the Airmega 400. The indicator on the filter lets you know when the pre-filters need to be cleaned. This will vary depending on how polluted your home is. To remove any debris, I simply run my hand vacuum across them. Coway recommends wiping down the pollution sensor and vents with a soft, dry cloth once every two months to maintain a clean environment.

There are some cons to be aware of. It is also very quiet on the lowest setting. This is still quite powerful. Amazon

HEPA filters are the most expensive part of an air purifier. The replacement filter set for the Airmega 400 comes with two filters, but it is priced at just $50 on Amazon. This can make it expensive to maintain. Although you will only need to change the filters once a year, it is still an ongoing expense.

The Coway 250 is my top-of-the-line air purifier. It performed well in comparison to our top picks for air purifiers. However, it was not as efficient at eliminating VOCs from the air. For more information on the best air purifiers, I recommend that you read this guide.

The bottom line

I was overall impressed by the Airmega 400. This was tested in spring when pollen counts were increasing. I noticed that my eyes were more sensitive and I was sneezing less. The Airmega 400 is a great device for clearing out vape clouds, smoke and dander. The best part is that it operates so quietly, I barely notice it.

All Coway air purifiers are excellent at fighting indoor pollutants. I highly recommend them.

What model should you choose?

The Airmega 300 and 400 are best suited for large spaces where you need to get rid of irritants. The 200M is a good choice if you have a small space and want the ability to move the purifier from one room to another. The 300S and 400S are also options if your purifier is part of your smart home setup.

The pros: It runs quietly, cleans the air in an area of 760 square feet in 15 minutes, is energy efficient and has an attractive design

Cons: More expensive replacement filters that are not as effective in removing VOCs.