Vital 100S-P

I had to look through your profile for clues - I'm guessing you're in the UK? Shark is low quality. They're dishonest in their marketing (e.g., "NeverChange" filters schtick is bogus). We've seen numerous problems with the air quality display not working. And if a model is discontinued, filter availability afterwards can be pretty short. I assume by "dust", you're allergic to dust mite allergens? If you haven't already, you'll probably need to take multiple approaches to controlling dust mites. This includes washing bedding in hot water every week, using allergen covers on mattresses & pillows, wet-dusting with quality microfiber cloths, and keeping relative humidity (RH) below 50% for prolonged periods. Dust mites can't survive in low humidity environments. With significant allergies, I'd use a bagged vacuum with a HEPA exhaust filter such as Miele or Sebo. Bagless vacs are often leaky. Obviously an air purifier will only help with airborne allergens and not the ones settled on various surfaces. **For rooms measured in meters, I would seek out a Clean Air Delivery Rate (CADR) 6 times greater than the room's volume. So** ***if*** **your ceiling height is 2.4 meters, this means your room's volume is 60 m****^(3)****. 60 m****^(3)****/h × 6 = 360 m****^(3)****/h. You need a CADR of at least 360 m****^(3)****/h.** Coway is one of the highest quality consumer-grade brands. And yes, they're more expensive. However, Coway units tend to be more energy efficient and quieter than others. A recommended model would be the [Coway Airmega Jet](https://en.coway.com/products/airmega-jet-1). Top CADR is 402 m^(3)/h. The [replacement filter is £59.99 directly from Coway](https://en.coway.com/products/airmega-jet-filters?variant=40840000077917) (GreenHEPA + activated carbon). Filter set is a bit cheaper on Amazon currently. If you were to go with Levoit, I'd buy *two* [Levoit Vital 100S](https://www.amazon.co.uk/Purifiers-Bedroom-Washable-Quality-Allergens/dp/B0CLY1ZG1F/?th=1) units. This is because top CADR is only 243 m^(3)/h. Important: keep in mind the CADRs listed for these purifiers applies to the highest airflow/speed setting only. Lower settings have lower CADRs, which reduces cleaning effectiveness.

For rooms measured in meters, you'd want Clean Air Delivery Rates (CADRs) 4 to 6 times the room's volume (in m^(3)) for someone with asthma. Therefore CADRs should be 135 - 202 m^(3)/h. The Levoit Core series purifiers tend *not* to be as reliable as the Levoit Vital series. I think you only have the [Levoit Vital 100S](https://levoit.co.uk/products/levoit-vital-100s-smart-air-purifier) in the UK, so I would recommend that model. Just keep in mind the particulate CADR is listed for the highest airflow speed/setting only. Lower settings have lower CADRs which reduces cleaning effectiveness.

Not a big fan of the Levoit Core series purifiers. I think the Levoit Vital series and the EverestAir model are superior because they use separate permanent pre-filters. That and I've read about more issues (malfunctions or unit failures) with the Core series. Ultimately the right purifier depends on pollution levels, health conditions like allergies, and room volume (length x width x height).

Levoit is lower quality than Coway. I think the Levoit Vital series purifiers and EverestAir purifier are quite good (definitely better than the Levoit Core series).

The stuffiness you describe may due to higher indoor relative humidity (RH) and/or carbon dioxide build-up. High RH can lead to mold and mildew growth, which in turn produces odorous mVOCs (microbial Volatile Organic Compounds). Purifiers only capture *airborne* mold and mildew; they can't mitigate moisture sources or pathways. A dehumidifier would be much better instead. I'm guessing you have one or more ductless mini splits for air conditioning? Unfortunately "whole home" dehumidifiers require ductwork. You would need to buy a freestanding dehumidifier instead. I'd prefer the Levoit or Philips over Xiaomi or Blueair. Just keep in mind that Clean Air Delivery Rates (CADRs) are typically given for the highest airflow speed/setting *only*. Lower settings have lower CADRs, which reduces cleaning effectiveness.

The results would **not** surprise this sub. The CBC News video you linked is common knowledge. The CBC team selected some pretty lousy purifiers to start. Dyson is terrible and pure marketing; most of their purifiers have low particulate CADRs relative to price. The Levoit is a very small unit. Neither the GermGuardian nor the Honeywell are very powerful. Only the Blueair has good CADRs, but it relies on an always-on ionizer to enhance the mechanical filter's efficiency. Regarding what to look for... The AutoModerator comment mentions the importance of Clean Air Delivery Rates (CADRs). Our [FAQs wiki page](https://www.reddit.com/r/AirPurifiers/wiki/index/faqs/) mentions CADRs 16 times. Our [Buying Guide for particulates focused purifiers lists CADRs](https://docs.google.com/spreadsheets/d/16bOQoFE9rKYMlo1AR_cged3yRpxfmiey54U65UeBCR4/edit?gid=0#gid=0); ideally these include dust, pollen, smoke, and PM2.5. The [AHAM 2/3 rule](https://ahamverifide.org/ahams-air-filtration-standards/) is listed in multiple places. The link to Harvard's [Portable Air Cleaner Sizing Tool (PACS)](https://www.reddit.com/r/AirPurifiers/wiki/index/calculatorsortools/#wiki_portable_air_cleaner_sizing_tool_.28pacs.29) in our wiki helps you explore CADRs while factoring in room ventilation. And yes, the DIY air cleaner comprised of MERV furnace filter(s) plus box fan is very well known. Most MERV filters are less restrictive than HEPA filters, allowing for more passes through the filter media in the same amount of time. But IMO using just one MERV filter is sub-optimal. The more effective DIY cleaner is a [Corsi-Rosenthal box](https://engineering.ucdavis.edu/news/science-action-how-build-corsi-rosenthal-box). This typically employs four MERV filters. I've recommended them many times and C-R boxes are mentioned several times on the FAQs wiki page. However, many people will find a box fan very loud. A highly energy efficient and quiet variation would be a C-R box with PC fans. See the article ["PC Fan Corsi-Rosenthal Guide"](https://itsairborne.com/pc-fan-corsi-rosenthal-guide-a611dabf7e0c) from the *It's Airborne* blog. There are also various products or kits out there requiring some amount of assembly: [Clean Air Kits](https://www.cleanairkits.com/), [North Box Systems](https://aidankepo.wixsite.com/northboxsystems), [Nukit Tempest Pro - Complete](https://cybernightmarket.com/products/the-nukit-tempest-pro-complete-air-purifier-kit-usa). And lastly... linked in the right sidebar is r/crboxes.