Alen Breathesmart 75i vs Coway Airmega 400S Comparison

Through this Alen Breathesmart 75i vs Coway Airmega 400S comparison, you’ll be able to understand the core differences that relate to both the price and features of these air purifiers. Inside this post, you’ll find some other cheap air purifier alternatives from these and other brands. 

It is getting harder to inhale good, fresh hair. In today’s world, it has become a very serious issue for many people. Yes, the air is a gift to all. In reality, though, is this gift really free?

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Some Other Top Rated Air Purifiers To Consider

  1. NuWave OxyPure Smart Air Purifier
  2. TaoTronics HEPA H13 Air Purifier for Home
  3. GermGuardian AC4825w air purifier
  4. Honeywell HPA300 air purifier 
  5. Alen BreatheSmart T500 True HEPA Air Purifier

The degradation of the environment with dangerous gases and poisonous substances poses serious health issues to people. 

These pollutants circulated in the atmosphere daily affect numerous lives. This way, money for feeding families is channeled into treating ailments from pollution.

Nonetheless, all hope is not lost for the world. there are ways to make inhaled air safe for the home and environment. This can be achieved by using purifiers of air. These relinquish the dangerous gases, dust molecules, and diverse smells in the home.    

You might be curious to know what all the fuss is about purifiers. You needn’t worry. It will be unveiled soon. However, what products will be most productive, you may ask?  Do not fret. That question will be answered here just for you.  

Below are the quick links to the products contained in this air purifier comparison.

Purifiers tend to be costly. Hence, before thinking of putting your money in all the way, you should know what is most suitable. It is good to carry out research.  

This article will compare two top-notch purifiers used to clear large rooms. These two are Coway’s ”Airmega”, and the Alen ”BreatheSmart” classic large room air purifier. These products have beautiful designs. They also work perfectly to make the room’s air as clean as possible.

Alen Breathesmart 75i vs Coway Airmega 400S Comparison: The Buyer Guide 

You will be surprised to know that your air indoors is usually worse than that outside. The fact that we are more indoors than out, puts one at great health risks.  

Purifiers come in handy here to produce fresher, better air for the home and office space. This way, staying indoors has no risks at all. 

 So, before purchasing a purifier, below are some questions you need to ask yourself:  

1. What Is My Reason For Wanting A Purifier? 

Purifiers help clear out indoor spaces polluted by dust, pollen, and dangerous gases. By creating a space free of ragweed, mold, dander of pets, and all, the environment is healthy. 

However, you should know that many types are patterned to suit specific needs. These needs or purposes are:   

  • For allergies: For this problem, a purifier made to relieve allergies is your best bet. they comprise numerous filters to neutralize allergens indoors. This filter includes the HEPA.  
  • For Asthma: Are you asthmatic? Or do you have its symptoms which chemicals and odors trigger? If this is you, then you should get a purifier for asthma. Or, consider a purifier against odors and chemicals. These kinds contain filtration for the chemicals and odors. They also contain filters like HEPA to remove allergens.    
  • For Smoke: For smoke, there are designed purifiers. These evacuate soot, smoke, and such fumes. If this is not the case, standing respiratory health issues could be heightened. the environment can also reek with odors that are not pleasing. 
  • For pets: Specific purifies are available just for dealing with pets. They eradicate pet hair, dander, and smells.    
  • For Sensitivity to Chemicals: You should consider getting a purifier to neutralize chemicals if you are susceptible to such. Purifiers like these have more chemical/odor filtration. Also, they are usually made using contents that won’t release other chemicals to the atmosphere and thus worsen your sensitive nature.      

2. The Size Of Air Purifier You Want

You have to know the size of your room, to decide on the perfect size of the purifier you need. This measurement is taken in square footage.  For example, Coway Airmega 400S is about 1560 sq ft. 

Are you allergic or asthmatic and need an air purifier to aid you with the symptoms? If this is you, you ought to consider changing the air of the purifier every hour. This is called the ”ACH” rate. The ACH is the frequency with which the purifier can sort out the air volume of the space every hour.    

Purifiers able to filter the space for up to four sequences in an hour are perfect for people dealing with asthma and allergies. These four changes in an hour purify the purifier to work thoroughly. This way, microscopic allergens that trigger symptoms are filtered out, so you can breathe easily.    

These purifiers being considered here have the size of four changers for an hour. However, the following guides will further support your choice:   

  • Small Size: Such are made for confined and personal spaces of about 299 square.  
  • Medium Size: This is good for spaces having feet ranging from 300 to 699.  
  • Large Size: This should be used for rooms of about 700-1900 feet.  
  • Whole-House Size: For this, look into our models for such.  

3. Your Preferred Air Purifier Features 

You should be concerned about what specific features you want in a purifier after size/type.  

Some of such features to look out for are:  

  • EPA has highly rated some purifiers as money savers and energy conservers; these should be used.   
  • There are purifiers using Wi-Fi that can be regulated from a mobile device you would like.  
  • There are some purifiers that have indicated that give updates about the excellence of the air in your space.    
  • Some other attributes to look out for are: Purifiers with controls hold mobility, various fan swiftness, filter indicators, etc.

4. Location For The Purifier  

Usually, it is recommended you put the purifier where more time is spent, which is the bedroom.  

Do not forget that purifiers are made mainly to cleanse the room’s air. Thus, it might be pertinent to purchase purifiers for more rooms and locations.  

More so, you might decide to put wheels, remotes, and other useful features in a unit to make it more mobile from one room to another.    

Purifiers that cover the entire house are getting to be more utilized in cleansing all rooms in the house. It is the fourth kind of purifier as it pertains to size, as discussed above. The HVAC pattern already existing in the home for cooling/heating the home is connected with the purifying units.   

5. What About Maintenance For The Purifiers?  

What is most necessary in maintaining purifiers is to replace their filters for air. now, you might want to know the frequency with which they should be replaced. These will be noted below according to the type of filters:    

  • HEPA: These filters can last for a year according to how it is used. In fact, some brands have a duration of five years like the ”IQAir HyperHEPA”.
  • Carbon: These filters last for six months.
  • Pre-Filters: These can stay up to three months. Nonetheless, some of such filters can be washed for lasting filtration.  

Some other kinds of purifiers utilize ultraviolet/heat to cleanse the air, as well as kill allergens/ germs. Those types do not need you to disturb yourself for the replacement of filters.  

Airmega 400S vs. Alen BreatheSmart 75i Air Purifier Comparison

Though costly, there are two of the most sophisticated purifiers that are just aesthetic and highly mechanized. they can be automated due to smart mechanisms not needing human help.   

These two are to be considered in this section. For this, an Alen Breathesmart 75i review will be placed vis-à-vis a Coway Airmega 400s review.  Points for this comparison are: 

Checkmating the Air’s Quality

Both purifiers possess sensors against the pollution that monitor how pure the room’s air is. They possess LEDs which are colored lights that will help you assess the pollution level. Such monitoring is automated and continues throughout the day. the only time it will stop is when both units get put off.   

Related: GermGuardian Elite 28 HEPA Tower Air Purifier Review

Its Modes

Airmega has 3 modes. These automatically fit into the condition of the room’s air. Firstly, there is the ”Auto” mode which fits the speed of filtration and fans automatically to get a cleaner room. Second is the ”Eco” which puts off your fan just for some minutes if the air in the space is perfect.

The third mode ”Sleep” possesses sensors of light that note the dark state of a room. It then allows for a switch into a calm setting that lets you sleep well. 

You should know that 400S possesses a timer you can program and time for its entire process of purifying.  

The Breathesmart purifier has two modes that are in operation. They are the auto and the manual. 

The product also has four-speed patterns for its fan: turbo, low, high, and medium. These work with those modes mentioned above. For ”auto”, the device reacts to levels of pollution of the space and mechanically changes to any one of those four. 

You should know that there will be a change in power speed if the air gets highly polluted. This is because it will be quicker and grasp more air.   

Alen Breathesmart 75i manual mode can be programmed to work effectively. A timer can be set for operations within a duration, so that a ”start” time is fixed. More so, 75i gives a calm sound that aids sleep.    

What kind of Noise

The two units can be classified as quiet when placed vis-à-vis other purifiers. For BreatheSmart, there is an inbuilt WhisperMax system that cleanses large air amounts, without much noise.  However, the greater the speed of the fan, the greater the level of noise. The noisiest is definitely that of turbo speed. Airmega is quite quiet too when set very low, and quite loud when set very high.   

The Process of Filtration

For both filters, the processes are different. Airmega has a double filtration mechanism that consists of a Max2 and a pre-filter. The latter is created using the micromesh that aids the eradication of dust, fur, and hair.  

Max2, however, projects as a real filter of the HEPA. It traps contaminated air particles of microns equal to 0.3. Plus,  it is made with carbon to limit explosive compounds/dangerous fumes. Some of such are ethanol and ammonia.     

Airmega also has an indicator of its filter. This notifies you about the need to change your Max2 and cleanse your pre-filter. The maximum coverage available for cleaning is about 1560  Also, the whole area cleaning is done within every half hour.   

BreatheSmart possesses a double filter mechanism which has a pre-filter that can be washed and traps big particles. It also has a HEPA system that is charged in an electrostatic way and traps over 99 percent of mini pollutants. 

There is also an added layer called ”antimicrobial” which stops the expansion of fungi/bacteria. This is also jammed with active carbons that terminate dangerous chemicals, smoke, and polluting odors.     

One other special attribute of 75i is its ionizer’s ozone that electrifies the air particles. This lets them be lumped together so they can be captured easily. There also exists a timer for the filter’s lifetime so you know when your HEPA is to be replaced. BreatheSmart covers a maximum of about 1300 feet. it cleans itself every half hour.  

Related: Blueair Blue Pure 211+ Air vs Germguardian AC4825 Reviews

The Smart Level of The Technology

In terms of this feature, Airmega 400s is usable remotely with the help of an app on your mobile device. This cannot be done with the BreatheSmart. Wi-Fi is usable with Airmega allowing you to make adjustments via an app called the ”Coway IoCare”. 

This lets you observe, schedule, and monitor warnings from your device. You should know that it works in hand with Alexa from Amazon; this means that vocal instructions can be obeyed.   

The two units can be trusted to purify the air in big rooms. Nonetheless, Airmega is slightly more advantaged due to its smart mechanism and allowance for vocal instructions.  but, choosing any is still okay.

Some Other Air Purifier Comparison 

GermGuardian AC9200WCA Air Purifier  

When segments have a range that is low, they can be quite competitive among the best air purifiers on Amazon. Here, we know the industry ”Guardian” as very popular for being quite affordable.

This purifier under consideration is an American brand known for affordable, energy-conserving, top quality and secure products for use.  

GermGuardian is the most recent project in the industry to have healthy competition among segments within the middle range. It joins efforts between the HEPA and the light of the UV-C to trap pollutants and kill bacteria/germs in them.  The light, though not dangerous to humans, can tamper with the dominant DNA information of viruses/germs. It can also terminate them entirely.     

Now, the fan-power availability helps the purifier cover rooms of about 335 feet excellently. this, it does with the verification of AHAM.    


  • The ratings of its performance are excellent. 
  • It filters air properly. 
  • It is great for segments having low ranges. 
  • Its warranty is for five years. 


  • At its highest level, it can be noisy.
  • It doesn’t possess smart characteristics. 

WINIX AM90 Air Purifier 

The former holder for Winix had a cleaning mechanism for air in five stages. However, in reality, such anti-microbial activity is not that necessary. More so, AM90 gets the advantage of novelty, plus a backing zeal to push it to the ”best-purifier” position.  

The brand cannot be overlooked in the quest for a purifier. It has been in the U.S markets for over 15 years. 

It is based in Korea and is a wonderful solution against numerous allergies of pets. What more? It is high-tech and very affordable. The WINIX AM90 also has a good filtration mechanism and is tested and trusted by top regulatory bodies like CARB.  


  • Its ratings for performance is excellent. 
  • It is peculiar, efficient, and a secure PlasmaWave tech. 
  • It has smart attributes like Wi-Fi links and sensors. 
  • It is unbelievably quiet. 


  • It can have an issue with its wireless connection. Possible problem with Wi-Fi connection
  • It has to be kept far from other electronic devices. 

Honeywell TRUE HEPA Allergen Remover HPA300

This is also a budget-friendly option for you. It has an effective cleaning system that is free from ozone. This system is acclaimed by CARB as a wonderful device. 

Its pre-filter possesses carbon that is activated. This helps to sap in VOCs, odors, and gases, and also trap bigger particles.

HEPA can trap about 99.97 percent of pollutants of about 0.3 measured in microns. Such pollutants are mold, pollen, bacteria, plus dander of pets.  

You should rest assured that this product utilizes the perfect HEPA filtration mechanism around the globe. With just a layer of this filter, HPA300 stands with Coway when it comes to power.  

The filter (HEPA) can trap about 0.005 viruses in microns.  

For size reduction, Honeywell combines the carbon active filter with your pre-filter. However, the latter should be changed every three months. Sadly, it puts Honeywell at a disadvantage due to its high cost of filter change.  

Though in the range of low segments, Honeywell makes use of great fan efficiency. This, plus ACH and CADR that goes above the medium range of purifiers. Hence, this product can take on large spaces of about 465 feet. AHAM validates its efficiency.   

But, this purifier produces great noise because of the power of its fan. Also, though it is its company’s game-changer, it lacks some relevant smart attributes.  


  • It has a great rating for performance, plus a real HEPA filtration system. 
  • It has a powerful fan level–ACH and CADR.
  • It runs a budget that is low in range.
  • It covers rooms of about 465 feet. 
  • It has a warranty of up to five years. 


  • It does not have smart attributes. 
  • It can be quite noisy.
  • Replacing its filter is an additional cost. 

Coway AIRMEGA 400

This is one of the most costly purifiers from Coway. Attached to it is a Max2 filter which increases its efficiency without emitting any zone. 400S can be called Coway’s flagship, but that of 400 puts in most of the catchy attributes into low price sums.   

Coway’s line-up has just middle to high-level purifiers that operate with great fan efficiency. The 400 can cover up to 1560 feet. That of 300, however, falls to just about 1256 feet. The good news is that all their costs fall presently; hence, you can purchase quality flagships easily.   


  • They have quality performance acclaims. 
  • There is a proper structure having materials of top quality. 
  • There are superb fan efficiency and technology. 
  • It is very quiet.
  • It has a warranty of up to three years. 


  • The application has received negative testaments. 
  • Replacing its filter can be costly. 


Can air purifiers be harmful?

Yes, but only if they are faulty and, that way, they lead to health challenges. Purifiers with filters give no dangerous particles, making your health safe. Dangerous particles that can cause allergies are not in the inhaled air because the purifiers remove such.  However, generators of ozone are bad and can be harmful.  

How long does it take an air purifier to work?

It should be in operation all day because airborne pollutants and dust circulate all day. A purifier cleanses a space from between half an hour to two hours.  

Do air purifiers emit radiation?

Ozone is not emitted from purifiers using only HEPA kind of filters for air cleansing. Purifiers that ionize manufacture ozone due to electric power. Users have made it known that imminent dangerous ozone layers can be produced.   

Where should I place my air purifier?

It is best to give a bit of room on top, sides, and front for maximum efficiency, Electronics with wavelengths that are alike can lead to interference. Hence, be sure to keep purifiers away from microwaves, sound sets, and TVs.  

Is it safe to sleep with an air purifier on?

Yes. Purifiers give you quality air in the sleeping area. Hence, you inhale the fresh air, sleep quicker, and more soundly.  

How do I know if my air purifier is working?

When debris, dust, and hair clog up your filters, you know the purifier is operating well. But you might need a replacement if your filter is too dusty and dirty. You should know that such only operates for HEPA kind of purifiers because filters using carbon won’t show aging.   

Where can I buy an Alen Breathesmart 75i air purifier?

If you go through the Alen Breathesmart 75i air purifier review in this post, you’ll see a link that leads to Amazon. Follow the link and you’ll arrive on the product sales page where you can place your order. Every other product reviewed can be bought from the same source. 

Related: Colzer 1556 Air Purifier Review And Buying Guide


In conclusion, the two devices are great for purifying the air in big spaces continually. Nonetheless, the 400s supersedes the 75i an advantage since it is a mobile application smart and responds to commands.  But any of them you choose to go for is fine. Just know what you want, and go for it.  

Following through the product links above will lead you to the sales page for each of the products mentioned here. There you can ask more questions to get clarifications from some other experienced buyers and users. Don’t forget to check the return and replacement policy before clicking the buy now button. 

Related: Coway AP-1512hh vs Winix 5500-2 Comparison

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