AirFanta 3Pro

Since you said the bedroom is "not huge," and since dogs have sensitive hearing, I would recommend an Airfanta 3pro (non-carbon) over a CR box. Similar design but it's smaller and quieter, and it fits your budget perfectly. I believe it's still $152 with the code HOUSEFRESH on their website.

The AirFanta 3Pro uses E11 filters (95% interception efficiency at the MPPS), whereas HEPA is 99.95% or 99.97% interception efficiency at the MPPS, depending on the standard used (US or international). Previously E11 was called H11 and *was* considered a "HEPA filter," but that has since been changed. The inventor chose this filter because it maximizes the overall CADR, so switching to a HEPA filter would actually make the filtration worse. https://x.com/Engineer_Wong/status/1899144721710408038 --- EDIT: Yikes, big pile of misinformation linked by /u/Justifiers below. And a nice downvote too for my troubles, probably thinking (wrongly) that I downvoted them. To save people watching a rambling conspiracy video (skip to 6:20 on the second video if you want), the YouTuber's objection to CADR is the data only goes down to 0.5 microns and not smaller (untrue, PM0.5 by definition measures *all particles smaller than* 0.5 microns, and also misinformed because at that size electret filters get *better* interception efficiency as the particles get smaller) and one RTINGS.com video which appears to show CR boxes performing worse than HEPA filters with lower CADR (contradictory, because elsewhere in the videos he extensively blasts YouTuber tests as unreliable and amateurish). Save your time and brain cells. Tl;dr yes **CADR is still what really matters** and not HEPA.

At fan speed 2 the 150's performance falls to CADR = 78 CFM, so HouseFresh doesn't recommend it for room sizes larger than 117 square feet. https://www.youtube.com/watch?v=gJWJX-FMxeo I'm not sure why anyone would recommend the IKEA Vindstryka because it's just an air quality monitor, not an air purifier. I wouldn't recommend the IKEA Starkvind either, because its noise and performance is similar to what you already have. Returning the Coway and getting an Airfanta 3pro might be a good option. I'm not sure about Auto mode on your Coway, but I would expect that ramping up when it detects particles and then ramping down when the air is cleaner so it's quiet most of the time is exactly what you would want? Take care.

Obligatory recommendation for the AirFanta 3Pro. One of the best CADR-per-dollar and CADR-per-decibel options out there, and it doesn't have an ionizer which is bad for birds.

Smoke is tiny *particles* of carbon and oils. If you're getting second-hand THC ("hotboxing" effect), it's the particles not the VOCs. You just need lots of particulate filtering CADR. Try getting an AirFanta 3Pro and setting it on 70% all the time. You might still smell it occasionally, but it shouldn't cause any psychoactive effects. Also, incense and candles and sprays are really bad for your health (almost comparable to cigarettes). https://dynomight.net/air/ --- EDIT: to the one who downvoted, please provide evidence of only cannabis VOCs causing second-hand intoxication. If I'm wrong I wanna know it, and I'll gladly fix it.

Oddly people forget "perfect is the enemy of good." 5500-2 or AirFanta 3Pro will be a massive step from nothing at all. If an open window isn't an option, exhale directly into the intake for maximum effect. Toke on buddy

AirFanta 3Pro, or just buy the filters and print up your own DIY [AirPhantom](/r/crboxes/comments/1oqinjr/3d_print_cr_box_for_airfanta_3pro_filters/) (I recommend PureWings 3 High Speed for the PC fans). Good CADR-per-decibel and CADR-per-euro, and it has infinitely variable fan speed.

Always a fan of the AirFanta 3Pro. Good for pulling out particles at low cost and low noise.

AirFanta 3Pro. As soon as you said "budget not a huge concern" the usual Medify / Alen / random $800 purifier sharks began circling, but for quiet yet powerful particle filtration it's hard to beat the 3Pro. https://housefresh.com/airfanta-3pro-review/

DIY CR box or AirFants 3Pro. You need a lot of airflow to do anything at all about dust, and these are the most economical options. For the CR box use 3M 1900 filters, four 20x25x1 or 20x30x1, get whatever's cheapest per square inch. BJs online usually has a good deal. Use the Airfanta if electricity prices are high in your area, because it uses a lot less energy. Cheapest price is on their website with code HOUSEFRESH, it should come to $152. Don't bother with the carbon version since it has lower particle performance and the carbon gets smelly long before the particle filter reaches end-of-life. https://cleanaircrew.org/box-fan-filters/ https://www.youtube.com/watch?v=IzxNaSP7c6I EDIT: ahh, I see you are in Italy? The Airfanta is probably the best option then, since in most of Europe 3M filters are only available through Digikey for higher unit prices, and generic substitutes tend to have many fewer pleats resulting in 2-3x smaller area of actual filter material. Instead of MERV 13 you might consider a CR box with the (European equivalent) M6 or F7 grade filters.

I wouldn't so much be worried about VOCs and odors, because *particulates* are the main health hazard from traffic pollution. Putting an intake fan with carbon but without particle filtration isn't the best idea. If anything, you would want to pass the incoming air through something like a Winix 5510 on Low, which has a HEPA filter that will remove 99.97% of incoming particles. You can literally tape (or 3D print) an AC window hose kit over the purifier intake. CR boxes are cheap and powerful, but also huge and loud. For any rooms where that matters (ie any room actually used by people), I prefer the Airfanta 3pro because it's small and quiet and low-power but still has almost the same cleaning performance of a big CR box. When it comes to *performance per decibel* the 3pro wins hands-down, and in the real world this matters a lot because people don't want their ears ringing at the end of the day because of their air purifier. So in practice a CR box is only ever run on Low (again except in unoccupied rooms, which are great for a CR box). Use the 3M 1900 filters if you make a CR box, they have many more folds so they pack 2-3x more actual filter material vs the generic filters. BJs online usually has the best deal, get a 20x25 or 20x30 size, whichever is cheaper per square inch (just make the box taller). To get "old, old windows" to seal as best they can, I recommend a thorough vacuum of the sill and frame area, wet wiping everything, wait for it to dry, re-locking it nice and tight, and then (for windows that don't need to open) Frost King makes a great non-damaging clear weatherizing tape especially for windows. This should also cut down a lot on traffic noise. 👍

Both. Lots of people will pitch you very expensive solutions, but generally the best option is the same: put 3M 1500 MPR or 1900 MPR in your HVAC system (no other brand or model, 1" or 4" both have lower resistance than standard filters, $10-12 if you get multi-packs online) and change it religiously every 3 months, and **also** run air purifiers 24/7 to achieve 5 air changes per hour at under 45 decibels such as Winix 5510 (200 sqft), AirFanta 3Pro (350 sqft), Levoit Vital 200S or SP (200 sqft), CleanAirKits Luggable XL (400 sqft), Levoit EverestAir (300 sqft), or Smart Air Blast Mini (400 sqft). Housefresh has data on sub-45 decibel performance. Lots of folks will pitch very costly systems, but this is what actually works. --- EDIT: I see now that you posted the same question in /r/ZeroCovidCommunity, so if you're going for **absolute maximum COVID protection** then I would double the requirements to 10 ACH, so simply cut all the square footage numbers for the air purifiers in half. You can also go up to 3M Filtrete 2200 MPR in your HVAC system (or higher if you have a 4" filter), but most importantly **make sure the filter holder is 100% leak-tight** using foam gasket material. Such leaks around the edges are usually the weak spot when it comes to single-pass filtration. Good luck, nice to meet a fellow zero-COVIDer "out in the wild"

Cooking odors are best addressed with opening a window (air purifiers don't do well with oil-based smoke), and very large dust isn't going to be captured. You're looking for about 286 CFM or 486 m3/h. For fine dust and diesel smoke from machinery, it's hard to go wrong with an Airfanta 3Pro especially at the price (and performance, and noise), or just a CR box using IKEA Starkvind filters and Arctic P14 PWM fans. These are the options with the highest performance per dollar, so I tend to reach for these first and then add more purification later if necessary. https://housefresh.com/airfanta-3pro-review/ A "productized" IKEA filter box: https://www.youtube.com/watch?v=ZjGJN57DgA8

Switchbot in the bedrooms and AirFanta 3Pro in the living room, most likely. If budget is really tight try the DIY options mentioned in the same HouseFresh article (most economical option is 3M 1900 at BJs online, 20x25 or 20x30 for the quad boxes and 20x20 for single filter). Note that these are rather loud (which matters more than people think) and rather large, so the non-DIY option is most likely preferable. https://housefresh.com/budget-air-purifiers/ EDIT to /u/unpaid-astroturfer who's playing offended for a (very sensible) preemptive block after they *open* accusing community members of being "marketers": lol, I wish! 😂 Despite that, "certified" purifiers are mostly just about whether the manufacturer has paid $15,000 to AHAM. The SwitchBot is relatively new (I'm eagerly awaiting the full HouseFresh review), but AirFanta has third-party test reports on their website if you're worried. Personally I trust HouseFresh and other independent testers.