From the brand
Welcome to KNKA store ~
Founded in 2005, KNKA specializes in environmental appliances including dehumidifiers, air purifiers, and humidifiers. With a professional design team and strict quality control, we balance performance with minimalist aesthetics. At KNKA, we believe clean air is the foundation of a happy life, which is why we focus on advanced technology and elegant design to create fresher, more comfortable living spaces.
Product Dimensions : 8.15 x 12.36 x 17.09 inches; 9.68 Pounds
Item model number : APH4000
Date First Available : August 22, 2025
Manufacturer : KNKA
ASIN : B0FNDG2TNK
Best Sellers Rank: #1,859 in Home & Kitchen (See Top 100 in Home & Kitchen) #10 in HEPA Filter Air Purifiers
Customer Reviews: 4.9 4.9 out of 5 stars (845) var dpAcrHasRegisteredArcLinkClickAction; P.when(‘A’, ‘ready’).execute(function(A) { if (dpAcrHasRegisteredArcLinkClickAction !== true) { dpAcrHasRegisteredArcLinkClickAction = true; A.declarative( ‘acrLink-click-metrics’, ‘click’, { “allowLinkDefault”: true }, function (event) { if (window.ue) { ue.count(“acrLinkClickCount”, (ue.count(“acrLinkClickCount”) || 0) + 1); } } ); } }); P.when(‘A’, ‘cf’).execute(function(A) { A.declarative(‘acrStarsLink-click-metrics’, ‘click’, { “allowLinkDefault” : true }, function(event){ if(window.ue) { ue.count(“acrStarsLinkWithPopoverClickCount”, (ue.count(“acrStarsLinkWithPopoverClickCount”) || 0) + 1); } }); });
𝐀𝐇𝐀𝐌 𝐕𝐞𝐫𝐢𝐟𝐢𝐞𝐝 & 𝐇𝐢𝐠𝐡 𝐂𝐀𝐃𝐑 𝐕𝐚𝐥𝐮𝐞: Certified by the Association of Home Appliance Manufacturers, this air purifier provides reliable performance with a Smoke/Dust/PM2.5 CADR of 226 CFM (384 m³/h) and a Pollen CADR of 242 CFM (411 m³/h). AHAM certification guarantees effective, high-speed air purification for your home.
𝐄𝐟𝐟𝐢𝐜𝐢𝐞𝐧𝐭 𝐀𝐢𝐫𝐟𝐥𝐨𝐰 𝐃𝐞𝐬𝐢𝐠𝐧: Engineered with dual front-and-back air intakes and dual side outlets, this purifier maximizes circulation for faster air exchange. Filters the air in rooms up to 3,500 ft² once every hour, making it ideal for large rooms, living areas, and shared spaces.
𝐃𝐮𝐚𝐥 𝐅𝐢𝐥𝐭𝐞𝐫𝐬 & 𝟑-𝐒𝐭𝐚𝐠𝐞 𝐃𝐞𝐬𝐢𝐠𝐧: Equipped with dual front-and-back cartridges, each featuring a three-stage filtration system: a washable pre-filter for larger particles, a True HEPA filter, and an activated carbon filter. 3-in-1 filter system traps everything from pet hair to microscopic particles, ensuring thorough purification. (Please remove the filter’s plastic packaging before installation.)
𝐏𝐄𝐓 & 𝐄𝐂𝐎 𝐌𝐨𝐝𝐞𝐬: PET Mode increases airflow to tackle pet hair, dander, and odors, refreshing the air in just 30 minutes. ECO Mode saves energy and extends filter lifespan by entering standby when air quality is excellent, then restarting automatically when purification is required.
𝐌𝐮𝐥𝐭𝐢𝐩𝐥𝐞 𝐌𝐨𝐝𝐞𝐬 & 𝐅𝐚𝐧 𝐒𝐩𝐞𝐞𝐝𝐬: Includes Sleep Mode with noise levels as low as 22-24 dB for ultra-quiet nights, Auto Mode for effortless adjustments, and four fan speeds for personalized comfort. Select the setting that suits your needs any time of day.
𝐑𝐞𝐚𝐥-𝐓𝐢𝐦𝐞 𝐀𝐢𝐫 𝐐𝐮𝐚𝐥𝐢𝐭𝐲 𝐃𝐢𝐬𝐩𝐥𝐚𝐲: A built-in sensor monitors indoor air and displays the AQI in real time. Color-coded lights make it easy to check your air quality in an instant.
𝐇𝐚𝐬𝐬𝐥𝐞-𝐅𝐫𝐞𝐞 𝐌𝐚𝐢𝐧𝐭𝐞𝐧𝐚𝐧𝐜𝐞: The filter replacement indicator notifies you when it’s time for a change. For optimal performance, replace the filters every 3–6 months. Use genuine KNKA filters (search B0FQNYGVZF on Amazon).
JosephK –
Pleasantly surprised — this actually helped!
I bought this KNKA air purifier because my room had this weird mix of dust + stale smell that just wouldn’t go away no matter how much I cleaned. I wasn’t expecting a miracle, just hoping it would maybe help a little.Honestly, after running it for a couple of days, the difference was pretty noticeable.Before: I’d wake up with a slightly stuffy nose and the room always felt a bit “heavy.”After: The air just feels lighter and cleaner. I don’t get that dusty smell anymore, and my nose isn’t irritated when I wake up. It’s one of those changes you don’t realize you needed until you experience it.It’s also much quieter than I thought — the sleep mode is basically a soft hum. I just leave it on and forget about it. Setup took like 30 seconds, and the controls are really simple.Overall, this thing solved the exact problem I got it for. Not fancy, not complicated, just does its job really well. And, most importantly, the price is very reasonable. Happy I picked it up.
Tim Y. –
Quiet and covers large area
I absolutely love this air purifier and definitely give it 5 out of 5 stars. It’s very effective, and the whisper-quiet operation, especially in sleep mode, makes it easy to forget it’s even on. It works well in any space. Setting it up was simple, and using it every day is straightforward. I also really like the size; it covers my living room (about 500 SF) without any issues. For the performance you get, it’s worth the price, and the replacement filters are affordable. The sleek, unobtrusive design fits right into my home without standing out. Please note it uses 2 filters, one in the front one in the back.
Harman Nahal –
Quiet, powerful, and great for large spaces
I bought this KNKA air purifier for my living room and it has been working really well. The airflow is strong and you can actually feel the difference after it runs for a while. The air smells fresher and the room feels less dusty, especially in the mornings.The AQI display is helpful because you can see the air quality change in real time. ECO mode is nice for nighttime since it keeps the purifier quiet but still active. Pet mode also made a noticeable difference with hair and dander from my dog, which is one of the main reasons I bought it.The washable pre filter is a big bonus. I clean it once a week and it catches a lot of the bigger dust and hair, which helps the HEPA filter last longer. The overall build feels solid and it is not overly heavy for its size.For a purifier that covers such a large area, it runs surprisingly quiet. Even on higher settings it is not annoying or distracting.Overall I am very happy with this purifier. It works well in big rooms, has useful modes, and keeps the air noticeably cleaner. I would definitely recommend it for homes with pets or allergies.
Summer E Zachary –
Awesome Air Purifier
I’ve been using this air purifier and I can confidently say it’s one of the best purchases I’ve ever made for my home. From the moment I turned it on, I could literally feel and smell the difference in air quality.The dual HEPA filters do an amazing job capturing dust, pollen, and pet dander — my allergies have practically disappeared! I have a dog, and before this purifier, there was always that faint “pet smell” in the air. Now? It’s gone. The activated carbon filter is incredibly effective at eliminating odors and absorbing cooking smells. Even after a busy day in the kitchen, the air stays fresh and clean.What really stands out is how quiet the unit is. On the lower settings, it’s barely noticeable, making it perfect for nighttime use. I sleep better knowing I’m breathing clean air. The design is also sleek and modern, so it blends nicely with my decor instead of looking bulky or industrial.I also appreciate the smart features — the air quality sensor and automatic mode work flawlessly. It adjusts fan speed depending on the air quality, so I don’t have to think about it at all. The filter replacement indicator is another great touch that makes maintenance super easy.Overall, this air purifier has truly exceeded my expectations. My home feels fresher, my sinuses are clearer, and the air smells pure and crisp every day. If you’re on the fence, go for it — you won’t regret it!