Core 400S-P

Just got 2 levoits. In NYC. Definitely less cooking/food odors in the home and a reduction in dust and soot from the window sill. Love them. Got the 300SP for bedroom and 400SP for living room.

I use this LEVOIT in both bedrooms https://a.co/d/4UdIxew I use this one in my living room https://a.co/d/am3GNeF

Ich hab den levoit core 400S auch mit aktivkohlefilter, ich kann ihn wärmstens empfehlen! Hätte es selbst vorher nicht gedacht, dass das so einen Unterschied macht.

Für mein Empfinden ja. Hab ihn nach ca.8 Monaten zum ersten Mal getauscht. Empfehle da aber eindeutig die original Filter, die billigeren Versionen waren Schrott.

I like the Honeywell HPA series - I have a HPA 5300. It is HEPA. I like that there are various pre-filters you can buy to tailor to your needs. I use a A pre-filter, an S pet-odor filter, and the standard HEPA filters. The unit circulates air in a large room about 3 times per hour. Noise levels are fantastically quiet, and the auto setting allows me to run the unit 24/7 without changing anything. While it’s lacking smart features, I don’t feel I need it. I also have a Levoit 400S-P that I run a different room, without the ionizer. It gives me comparable performance as the Honeywell but I don’t like lack of filter options, is slightly more expensive to maintain, and slightly noisier.

I bought this one! Huge improvement. Core 400s-p Levoit hepa sleep mode, 3 in 1 filter

You may want to make your own post. Please list the square footage of the livingroom/dining room/kitchen area. We need this to calculate minimum Clean Air Delivery Rates (CADRs).

The coverage rating is misleading marketing my Levoit. The 1,718 sq. ft. is at 1 Air Change per Hour (ACH). You need a bare minimum of 4.8 - 5 ACH. But that's not the most important metric. I would instead go by Clean Air Delivery Rates (CADRs). Using the [AHAM 2/3 rule](https://ahamverifide.org/ahams-air-filtration-standards/), the [Levoit Core 400S](https://levoit.com/products/core-400s-smart-true-hepa-air-purifier) has a Smoke CADR of 231 CFM. Therefore the largest room size it should be used in is 346.5 sq. ft., assuming an 8 ft. high ceiling.

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).

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.

Air sealing is your best friend. I wrote a big list of easy tips for air sealing common leaks [here](/r/AirPurifiers/comments/1iy1fzn/bbq_restaurant_opening_up_across_the_street_from/meurxjl/). Use GE #2 zero-VOC caulk, and I also seal around the electrical outlet gaskets too (just put the cover back on while it's still wet so it still fits, and try not to glue it on either). This results in 100% sealed outlets and switches on exterior walls. Your builder should have done all this, but the easiest time to double check is now. You need roughly 1770 CFM to achieve the *minimum* of 5 air purifications per hour, so I have to recommend about **six** [CR boxes](https://cleanaircrew.org/box-fan-filters/) (use 3M 1900 20x25 or 20x30 from BJs online) and/or [AirFanta 3Pro](https://www.youtube.com/watch?v=IzxNaSP7c6I). Both of these units achieve about 300 CFM on a reasonably quiet fan speed that is actually usable. Try to run them 24/7, maybe turning the bedroom units lower to sleep. If you can crank them to High in unoccupied rooms that would be ideal. Use the CR boxes (which are huge and noisy) in rooms that have extra space and aren't occupied very much, and the AirFanta (which is a 1 foot cube and much quieter) in rooms that are frequently occupied and where you don't want a giant air cleaner cluttering up the space. I believe the best deal is still on their website with coupon code "housefresh." You probably also want some sort of VOC carbon filtration. The easiest option there is the 8" AC Infinity Cloudline Kit. Tuck it in a corner of the kitchen and replace the carbon with fresh AC Infinity bulk carbon when you start to smell odors again (typically 3-6 months). This has 20 pounds of carbon for much cheaper than the typical $600-1000 purifiers like Austin Air or Airpura or IQAir. Sorry, I'm sure I must be leaving something out, but please ask if you have any questions or just want clarification. Best wishes --- EDIT: other options to consider are the Winix 5510 (125 CFM, $200), Smart Air Blast Mini (270 CFM, $700), Coway AP-1512HH (125 CFM, $150) or Levoit Core 400S-P (135 CFM, $220). These are all quoted at a reasonably quiet level (sub-45 decibels), because real-world usage shows most people don't like living with a jet engine.