Core 600S-P

Search high CADR purifiers. My recommendation is if you are ok spending the money on an iqair unit, to look at other options since you have multiple rooms. What I see right now is the levoit EverestAir on clearance for $299 from Bestbuy. It is an excellent choice with a high 350 CFM CADR. (I just got 2 more at this price) a “comparable” unit is the levoit core 600s-p(sale price 299 410cfm CADR) if the Everest is not on clearance. I would buy the core at the sale price. Owning both the Everest is better in my opinion. As others have stated multiple units will provide more benefit than one large unit. However again if you are spending that money and like iqair please consider the Atem-X as it has a very high CADR. Another option is the SmartAir blast MKII. This is a beast of a unit that targets commercial applications but is generally at the same price point as the larger IQAir units but proving a much higher CADR. I have one sitting in my 600sqft Great room.

I just ordered 2 of the Levoit 600S-P.

At least 3 Levoit Core 300-P or 300S-P (CADR 143) to support \~5 ACH for your sq. footage or 1 Levoit Core 600S-P (CADR 391). For the most even coverage, I would recommend the Core 300-P/300S-P setup.

Cheapest + most effective is a CR Box/Corsi Rosenthal box.  So you buy a cheap box fan (30ish bucks) + a set of 4 filters (such as filtrete 1900 - around 60ish) so for under 100 bucks or so....you get a very powerful air purifier with around 400 CFM power.  Levoits are excellent and I still have two core 300s on the corners of my living room..m but 1 core 300 is not enough power. ( I now have 8 purifers for a 1 bedroom apt as I need excellent coverage since I have an old carpet I inherited here with 5x kids of mold on an test.). But my air is crisp and clean now thankfully.  So you aren't going to have excellent coverage with 1 90 dollar Core 300.  You might need 3-4 of them for excellent.  2-3 might be "good" coverage, perhaps. (Or just one of they larger units like the core 600 or Everest Air but those are around 350-390 I think)  Point is the Core 300s have 155CFM so great for a small or medium room.  For proper coverage, given allergies and such, you will need likely a lot more than that.  As general CADR numbers are based off 1 air change per hour I think. But you want 4x air changes per hour for excellent coverage.  (Every 15 mins.) So a CR box will give you around 400 CFM m, for 90ish bucks, about the same as a 350 dollar bigger Levoit unit.   So I would suggest tape together a set of filters to a box fan....while you save up if you want a bigger Levoit. But that is cheapest way to get very good coverage.  Prob 1 CR box + 1 core 300 in bedroom.  But keep adding units as needed.  Also this doesn't mention sound.  For more quiet units those are more expensive, like a 1,000 Dyson that doesn't even move much air.   Or you could get a bigger pricier unit and run it on low, to still get decent CFM.  But you won't get both high CFM, and very quiet, for the price point you mention.  Although I don't find box fans loud pet se, and my purifiers to me are quiet, all running on high.  I have gotten used to it and actually like the background noise and don't even notice it.   (As compared to when I got my first Levoit Core 300 and noticed it more.)  So you will probably just have to get used to the sound, as that can just happen naturally after a while.   But again, sound is subjective so idk exactly what is "loud" for you.   But fans are in purifiers and all fans make at least a little noise pretty much.  So it's a trade off but vastly worth it...for having better quality air.   Other good brands are Winix and Coway, also as loud/quiet (depending on ones opinion) as Levoits.  They all perform pretty close and top 3 in recent testing for both performance + decibels.   So a combination of 1 CR box + 1 affordable unit will probably get you a decent amount of base coverage.  Then add another unit/upgrade from CR Box later if needed.  (You can also still keep using the CR Box for even better coverage or even putting 1 filter behind a box fan when upright normally...can also add to coverage and save  space.) 

I missed the last part of your post about considering a 350 range unit at top end.  So the Core 600 is I think 269 on levoit.com or around 300 maybe on amazon. So I would get the best unit you can afford...and then add a CR box/other unit when you can afford another. I am not a expert in dimensions, but using the calculator on the wiki page w 1,000 feet and 8 foot ceilings, and a target goal of 4 ach (air exchanges per hour) gives I think 466 CFM needed. Now they page actually shows 4 air changes per hour on the cusp between "minimum" (3-4ach) and "good" (4-5 ach)  and it says excellent is actually 6 ach.  (You would need 733CFM for that.) So the Levoit core 600 gives like 391-430 depending on dust/smoke/dander etc.  So you would be at at least adequate protection....with just a core 600, and on the cusp of "good".  So basically in your living room, best the unit, you will have very good protection. And in a bedroom or further away room still adequate.  So that would likely be a very good unit to get to start.  And whether you want to add a CR box or a smaller purifier in bedroom for more coverage later...you can find out.  (The Core 600 + CR box gets you to 800 range CFM units running on high, so that gets you excellent. Core 600+ a core 300 in bedroom gets you almost 600 CFM, so very good coverage that way too.) Remember, a bigger unit you can lower/more units run lower, will be quieter but get you equal CFM.  So the larger unit is the best way to go by all accounts.  And just add another later if you want/need excellent etc. 

Yes, I am aware and as per Google (via IQAIr source + others)  "Yes, ozone produced by air purifiers can be harmful even at levels considered "safe" or compliant with regulations. Ozone is a toxic, reactive gas that irritates the lungs and respiratory system, causing coughing, chest pain, and worsening conditions like asthma, regardless of whether it is generated intentionally or by ionizers.  U.S. Environmental Protection Agency (.gov) U.S. Environmental Protection Agency (.gov)  +3 Why Ozone is Harmful Even at "Safe" Levels: No Truly Safe Level: Studies indicate that even small increases in ozone can cause significant respiratory discomfort, decreased lung function, and increased mortality, especially for sensitive groups like children, the elderly, and those with respiratory diseases." So yes the number is low, but it is not 0.  What is safe for "most" is not safe for every individual (and animal).  For instance I had a medical issue that is 1 in 4,000.  So even if 95% are fine...5% may not be.  (Or even 1 in a 1,000.). So why take the chance if someone has never owned an ionizing unit before ?  The bare minimum for a first time unit...is to at least have an on/off ability which blue air just does not have.  It might be a fine choice for even most people, but it won't be a good choice for everyone.  It's a risk for a first timer as they just wont know how they react to it.  As well consider that people might have multiple units running....and these tests are only done on 1 unit.  So if you have like 3,4,5 units all employing even a "safe" level of ozone...then you may be then getting above a safe level at that point.  As you will then be getting 3,4,5x as much ozone dose if you have multiple units running. It. As well the size of space also matters, as in one study they put a unit in a small bathroom...a unit which has the "safe" ozone levels under 50ppm or whichever metric...and even that created over the threshold to an unsafe level and what would be a level 2 safety smog alert.  (Not how the unit is intended to be used they acknowledge, but undoubtedly some people will be running too big or too many units ..and getting to possibly unsafe levels..even if each unit individually is tested "safe".) As well some say that no amount of ozone indoors is safe to breathe. (As IQAir seems to be saying and that "safe" level keeps going down further and further...so we really don't know what is truly safe, and certainly safe for most...is not safe for every person.). Especially for their first unit.  It's just a flaw with BlueAir even if their units are good quality.   "Underwriters Laboratory’s UL Standard 867 requires household air purifiers to produce no more than 50 parts per billion (ppb) of ozone. However, even this level is not safe for humans to breathe." https://www.iqair.com/newsroom/are-you-polluting-your-home-ozone Note: I use a different brand one with ionizer, but I toggle it off sometimes. I like the function, so that works for me. But for a first time buyer...it must have toggle on/off otherwise it's a risk that they may not like the unit, or maybe even detrimental to thier health/animals etc.  

Unfortunately I believe the AirDoctors also have an ionizer that can be toggled on/off.   (According to Google search, and the panel I see.). So given the risk of even accidentally turning it on....(And forgetting/not knowing to turn it off...) id also consider avoiding this unit for your particular case.  Although otherwise they seem like good units imo.   Levoits are good units that don't have ionizers (save for their "plasma pro" line.). The Alen Flex line does not have them, and perhaps some Winnix/Coway units might not have them, but I am unsure of which.  Winnix will still work well without the ionizer, you just have to make sure you can easily tell if it's on/off,and i don't have one so idk how that goes.  When it says 630 sq ft 4x an hour on a device rated for like 2,500 sq feet then yea.  They already did the calculation for you so it's going to be good for 630 sq ft.  As opposed to the 2,500 or whatever would give it only 1 air change per hour.  Maybe you can ask your Vet if the ionizer harmful ?  But short of knowing for sure best would be fair to avoid a unit that has it, which would still be Air Doctor.  But look at the control panel and see if you think you could be confident in not toggling it on/off.  (Same for Winnix, those are great if you can handle not toggling the ionizer, th Air Doctor is prob also using the ionizer on its it's calculations, but I don't think it makes a big difference on CADR.  They do help a little though, but particles will fall to the floor so you don't breathe them in.  However particles still present + need to be vacuumed up. I run an ionizer on a brand where I can toggle it on/off.  It helps. But when I lay on my floor my floor is very dusty also...) So it's up to you how safe you feel with a unit you can toggle on/off but lots of units without ionizer, so id just look to one of those.  CR Boxes also great here as they give 400CFM power, with ofc no ionizer.  But otherwise I would look at bigger Levoit units like the Core 600 or Everest Air.  (Everest has similar CFM to the Core 600, but you pay more for a fancier air quality monitor, so Levoit core 600 is a great unit that has even slightly better coverage than the air Doctor (2,933 total to Air Doctor 2520, meaning the Levoit Core 600 will give you 4x hour in about 700 sq.ft. size.)  The Everest might have a slightly better filter too, but is pricier for around the same CFM power.  Winnix + Air Doctor likely great units too...but you gotta consider the toggle on/off thing.  

Yea, I wouldnt worry about tht true hepa thing.  Almost every brand in the market had been found to not be "true Hepa" if you manipulate in enough various scenarios.  Such as most units will pass Hepa 13 99.7% on low settings...but just turning it to high . Will then make the save unit not pass the threshold.  If it is a good brand it might be off by a fraction, do 99.5% instead of 99.7%.  it doesn't make much difference.  It will still clean the air well, as we see Levoits perform very well in recent tests.  It's more a technical thing, and a marketing thing with the better industry.  As top brands like Winix have also been sued for the same thing, as well as Alen, and many others.  Coway as well had not been sued yet ..but found to have the same issue, "not true Hepa" on some settings.  So they are trying to change their marketing...before getting sued. So If it is True Hepa on some settings, and not in others (by a fraction). Is it true Hepa ?  It be one a semantical argument.  But lawyers can make some money since they can technically prove it doesn't reach in black scenario.  As well Dyson was found to bring the suit against Levoit apparently...and the Levoits were found to clean more air per dollar spent than the Dysons themselves.   The only units that might meet that on all settings are the 1,000 Dysons or maybe IQAir.  The Dysons move are so slow...that they don't move fast enough to have that problem.  (They are known for being quiet and looking cool, but they don't move much air, and especially not for the price you pay.).  In recent testing all the top performing units have either been sued or had the same issue found...so it's more a marketing issue.  And not much of a difference to the user, if it's only off by a fraction...as it is with these good brands that we see lead on testing.  Heres some threads on the topic, and a YouTube video where they test all the units...2 of the units sued performed the best in the test...as it's not very important, and a technicality basically.  https://www.classaction.org/news/winix-lawsuit-alleges-air-purifiers-fall-short-of-advertised-hepa-protection-standards https://www.reddit.com/r/AirPurifiers/comments/1sh8696/are_coway_filters_not_hepa_on_all_speeds/ https://www.reddit.com/r/HouseFresh/comments/1s124ux/coway_purifiers_no_longer_true_hepa_or_green_true/ At around the 20:27 mark he shows the chart with the results...and picks the Levoits as one of the best.  They clean the air very well.  Excellent units, as I still have two of them in my living room going near continuously for 5+6 years now.... https://www.youtube.com/watch?v=sQGfO4hNb60

Very interesting.  Although it's not "no ozone" but under 5 ppb to meet that threshold.  So it likely releasing some, and is definitely generating a lot more ( in a chamber.). The thing, if there is even a slight problem with the unit, there could be leakage, so it's not worth the risk imo.  This response on a thread about it sums it up pretty well imo, and has a good link where they actually take the unit apart.   https://www.reddit.com/r/AirPurifiers/comments/we00oy/comment/j0mvtpw/?utm_source=share&utm_medium=mweb3x&utm_name=mweb3xcss&utm_term=1&utm_content=share_button This article might be exaggerating a little, as it's from a competitor (it even knocks Levoit, essentially hinting that they all have ionizers, which is ofc, not true.). However if a thing is generating a lot of ozone right near me, and that only thing stopping it from escaping is some tiny plastic in a low priced consumer item...I am not going to take the chance as sometimes purifiers break or don't work as intended.  (As the article talks about Sharper Image and Iconic Breeze etc.  Which went out of business.)  Blue Airs are good units.  But they definitely do produce ozone, however in a properly functioning unit (of that type) most units hopefully won't release most of it.  Also if you have it for a long time the chance of failure or something degrading increases so I would just avoid in your case.  But they are a decent brand imo.   https://smartairfilters.com/en/blog/blueair-air-purifiers-review-ionizer-ozone/

Yea, I would also say simple CR Boxes would probably help you a lot too (and your bunny) as it's just a 30 dollar box fan + 60 bucks for set of filtrete 1900 filters.  So 90 bucks for 400 CFM power.  About the same as a 300-400 dollar air purifier.  So it sounds like you could use a bunch of them.  But get 1-2 good units, with air quality monitor, filter replacement reminders etc. and maybe make 1-2 CR boxes as well, of you don't mind tht aesthetics...as you need excellent coverage it sounds like.  (I have 8x units in a large 1 bdrm apartment with old smelly carpets and some mold I inherited.  So even 2 good units did not solve my problem but I needed like 5 or 6 to get to comfortable, and 8 for for perfectly crisp + clean air.).  So add CR boxes too if needed and see if  you can get your bunnies snuggles to stop...Aldo Judy box fans can help more air around and help the efficiency of the purifiers.  But box fans with filters behind/in front/ or even takes sound them...all help exceptionally well too.  (Good merv 13+ filters, filtrete 1900 is one etc.) Purifiers will help you a lot....

Hmm, your right - that is pretty confusing.  I thought the S meant smart, but I didn't know what the P was. (I still don't, maybe "plus" ? But It might not mean anything really.) As there seems to just be s-p units and they don't have plasma.  (Plasma  One might officially be labeled s-p also but the all say plasma in the heading for those). One way to tell is the plasma ones have a little leaf button with +/- next to the leaf.  That's the Ionization button.  No normal s-p/or any normal units have that button on the top.  Only the plasma pro ones that specifically say that. (From what I just Iooked at.).  So the s-p should be fine. (Some I see 600S on an article but maybe that was an older version, or they were just using shorthand.) Bottomline seems you are corect that s-p is fine, googles AI is wrong, and I've only seen the ionization button on units labeled "plasma pro", as expected.  (My Core 300 units just say that,.no s, p, or anything so I think with newer units they have added the letters for whatever reason.)   

An affordable and long lasting one is Alen 45i, around 300-400 bucks and they have a lifetime warranty. (if you stay signd up with the filter replacement plan, with one every 9 or 12 months, your choice.) It has black carbon filter material, and is good overall, would be very good for a 300 sq foot area. Levoits are great for lonevity as I've had mine running continuously for 5 years...still going...most other affordable brands will break or have problems but the Levoits last forever. However, they dont have a huge amoount of carbon, only a litlte in some of the filters I think. If you can afford a lot consider the pricey units others are suggesting. I cant afford that and use a combination of levoits + an Alen + RIA Breezeguard (my best unit overall with carbon fiber layer + UVC + humidifier all built in, however it doesn't have a lifetime warranty but so far its been great after a few years. Around 400 I think. The RIA Breezeguard is bigger + pushes more air and has more options (also app/phone control.) But you prob wont need that so much in a small studio apartment. So if you want longevity/lifetime warranty and good effectiveness for the area you have...the Alen 45i is a good choice imo. If you had a bedroom then add a levoit in there for more coverage etc. The only downside to my Alen 45i is that it doesn't super forecefully move air on high, it just kind of goes pretty steady....but it lasts forever and for your small space, if placed in a decent spot where air is flowing...then would still be very good for now + long term. Add in more units once you move to a bigger space. You can also just buy some black carbon filters (for any brand really) and place a few around if you want to capture more odors, esp smoke. So Ria BreatheSmart great all-around unit with excellent features, good carbon, but unsure about longevity Alen 45i seems to meet all your needs with longevity, carbon, size etc. Levoits awesome for longevity as well (not lifetime warranty but they last a long time) but just so-so on carbon I think. (Don't know thier newer/more pricey models as my 2 100 dollars ones have lasted years....) Ofc I like all 3 brands and use all 3 in my bigger space (+ more in bedroom etc.)

I like Levoits myself, as well as Alen.  I've never had a Coway but people seem to like them too, and they likely perform well.  Dyson I think seems over priced for the performance you get, but it may have some other bells and whistles.  (The fan power on a Dyson for instance wasn't very strong in a comparison I saw, but yet they prob cost the most.  Maybe paying for aesthetics + brand name as well.)    Doesnt mean it's bad, just probably not the best value for what you get.   I also really like my RIA Breezeguard, as that's my current favorite unit I have.  (Don't know longevity yet though as it's maybe a newer brand and Ive had it 2.5 years vs 6+ for Levoits and Alen units usually have a lifetime warranty.)  If I was looking to get another unit I would definitely consider Coway, and if I could afford a Dyson I would consider that too.  But Levoits are affordable, reliable + last years.   Alens same idea but little pricier with lifetime warranty, and built to run continuously. (With yearly filter subscription enrolled.)  So no I don't think there is a consensus ?   As others are saying DIY it which gives good value for the CFM performance you get too. (but has some drawbacks as well.).  For instance I am disabled so I can't be messing with a unit if it has a problem, or putting stuff together, and I don't have the funds to buy a replacement if it breaks.  So I need something preferably  affordable, easy to use, reliable, and with excellent longevity/warranty.   So that's Levoit + Alen.  Other people will have other needs/preferences.  A lot of the well regarded brands units perform decently well, and have various small differences so it comes down to preference a lot. Just avoid random/new/cheap brands as those are the ones I've had break down and have the most problems.   

I keep two levoits in the corners of my living room,  but i also have an Alen in a more central location along a wall where a lot of air passes through.  But Levoits shoot the air upwards and are circular, so they sort of can work in a corner - but you still should have I believe 12 inches of space or so officially. (Mine are maybe 6 inches as I am not relying solely on either of them for coverage.) Ideal coverage i think would be near center of a room,  but also good to have it near where you are most of the time, and ofc its not always practical to put a purifier in the center of a room. (None of mine are.). So along a wall is OK, and in a corner can be OK esp if you have air movement, so I have a box fan next to one my corner levoits, to help circulate the air.  If it's just  put in a cluttered corner where no air will flow - then it won't be able to do as much.  So you will get better results if air can circulate through it with ease.  So put a fan near a corner unit and that can help offset that for instance. (A fan draws air in towards the back of it, and shoots air out the front - thus driving circulation.). So If you have at least some circulation.....corner units can be OK, but you do need at least a few inches of space from wall.  

If you can afford 800 then probably consider AustinAir, people on here seem to hold it in high regard and one of their good units is 750 I think.   I could never afford that, and have never had Air Doctor,.so I can't say anything on that.  I do love my Levoits but they are good affordable units, that last a long time.  If I had 750 I'd probably get an AustinAir, which has very thick filters and good for odors + VOCs.  (Levoits excellent, but more "normal" purifiers that get particles in the air, they have some carbon in filter but not as much as more expensive units.) Mid range options I could afford are Alen Flex (350+) and Ria Breezeguard (370).  Coways are also highly liked on here, but again, haven't had one so can't speak to that.  So for odors/VOCs id prob recommend AustinAir given that you are fortunate enough to afford it.   That's the one that I've seen recommended for odors/VOCs, and In your price range. (Or maybe 2 350 Alens, if you want coverage in 2 spots.).   The AustinAir filters are pretty expensive, some said theirs lasted years and some said they change them once a year.  My Alen Flex ones are about 90-120 and last me around 11 months avg.  And you get a lifetime warranty with the unit if you maintain the yearly filter replacement with them every 9 or 12 months.  But for 800 budget...look into AustinAir.  Edit: it looks like Levoits newer/larger units like Everest Air have a decent amount of carbon filter, so that's seemingly a decent all-around mid range option too.  But for VOC/odors specifically, Alens same price range units will still be a little better likely, and AustinAir even better.  

I second the 45i is a great unit, and they are sold at some hardware stores and such.  However I would also suggest getting the IQ AIr or Austin Air as well - as those are even better for VOCs - with many more pounds of carbon/charcoal pellets to absorb VOC gasses.  Alen will be the the best you can find at a store.  (They are good at both particulate and VOCs, but for VOcs you need to get it with their best filter, which is like 10-30 bucks more.). They also come with a lifetime warranty if you remain in the filter replacement program.  Although they don't move a huge amount of air so getting a Winix, Levoit, or Coway also a good idea to move more air/better/faster particulate capture.   The IQ Air and Austin Air also don't move a lot of air, so it's best to pair them with units that move a lot of air, so you get full coverage.  (Unless you could afford a lot of VOC minded units, but that is ofc very expensive.) So for me I have a mix of various brands with 2 Levoits, an Alen 45i, a Pure Enrichment Elite , RIA, and many others.  Some are good for VOCs, one has ionizer, and some are just strong for Hepa/participate coverage. In a basement id suggest a corsi Rosenthal box/CR Box.  As they don't look aesthetically pleasing....however for about 90 bucks....it will so about 400CFM power....which probably double the CFM power as all of those VOC type units do.  As VOC units move a bit slower....as that is better for the absorption of the gasses the charcoal/carbon pellets material.   Hepa-focused units will move air more quickly....so better for getting particulates and cleaning your air faster ..as they aren't focused in the VOC aspect (but can still help.). So I would definitely get at least an IQ Air or Austin Air for the VOC issue (they aren't in stores) a few Alens are down for general coverage+ effective at both, and then some stronger units for participate capture, which can be any of Winix, Levoit, or Coway.  All perform pretty similarly in tests of participate capture as the top 3 (with Dyson, which is overpriced for what it does but slightly quieter and with better sensors.).  But if you get a 30 dollar box fan and tape it to a set 4 merc 13+ filters...you get 400CFM power on high....which is as much or more than pretty much every consumer purifier under 400-500 bucks.  (And all the VOC units too.).  Lastly, ventilation for VOCs important as someone else said, so box fans great anyway.  Even putting a merv13+ filter behind a box fan...can help with CFM coverage and get you around 150Cfm...which is = to a 160 dollar air purifier about.    

I think the answer is both.  Although you can just put in a merv 15 or 16 filter yourself in the HVAC I believe, so you may not need to spend thousands of dollars there.   But the HVAC only runs at certain temperatures right ?  Vs air purifiers you can run them 24/7 all the time...for constant coverage.    That Lennox system seems cool, it's Merv 16 filters plus a PCO photocataltyic oxidation light purifier system.  Pco is in some purifiers too.  It can kill germs + converts VOCs into water vapor + carbon dioxide.  (VOCs are gasses essentially, stuff that creates odors, and sometimes even stuff we can't smell, that can still harm us.).  Idk what the data is on the light in that Lennox unit though.  Not an HVAC expert.  So idk if that's worth the money or not.  You can get PCO technology in purifiers such as PuraClenz, kaltech and others. Older  Uvc lights can produce ozone, but apparently newer PCO technology may not produce ozone.  One issue thigh, is that it might produce other unknown byproducts, when various chemical VOCs are converted.  So it's a new technology and IDK what possible compounds could occur.  I believe hfs generally considered safe thigh and I have two units.  (I use them sparingly and not daily like my other units.,) I would avoid the ion stuff as that will create at least a little ozone usually.  I am more comfortable with ionization in purifier units that I can easily toggle on/off.  So a larger unit like that might produce a concerning amount of ozone, idk, and it might or might not be easy to turn off.  But those would be things to consider there. The higher the merv generally good.  You want merv13+ I think esp for virus control.  So Merv 15 is very good.   I would avoid merv 11 as that might not capture certain viruses as well.   So it's a good idea to improve your HVAC, but you still want air purifier coverage for when the HVAC isn't running, I believe.  So you can get clean air with a lot of white hepa filter units they will capture virus particles.  Black carbon strips in fitness can Bind with smoke + help w smoke and odors.  Even better units for VOCs/odors will have like 10-15 pounds of carbon)charcoal pellets ..which absorb VOCs in the air.   You can try absorbing VOCs, or blasting them/covering them with PCO.  White hepa filters can't capture gasses so useless there.  But they are excellent at capturing partuculates, allergens, and viruses, if a good Hepa 13 filter I think.   So you have options.   But this a multiple approach as there are multiple needs.  I have 8x units in a large 2 bedroom apartment, each that does various things.  (One has ionizer, some are good for VOCs with carbon pellets, and some are just good for more HEPA coverage/particulate capture.).   I wasn't sure on safety with the PCO so I don't use those often, as that's a newer technology, and I test units before other people do.  If it were me, and I have the extra funds, I would consider the Lennox thing.  But can't say if I would get that or not.  As you can still get excellent air coverage just from people size + amount from air purifiers.   And you can buy yourself a merv 15 or 16 and prob put that in the HVAC yourself.  (Or have them but it's just a 150-180ish dollar filter, you don't NEED to spend all that money to have clean air.) But if you really want to be thorough....and you have the funds....and if you can toggle it on/off if there is an issue...then maybe consider that.  But you still prob need proper air purifier coverage too.   (I would avoid the ion stuff/merv 11 etc.)  Ionization fine in purifiers, for most, but can produce ozone and respiratory issue in some people.  So needs to be able to toggle on/off for first time user in my opinion.  Ionization can help particles bind together and fall to floor so you dont breathe them in as much.  It can help.  But you still then have particles on floor that need to be vacuumed up.  And some bothered by even small/safe amounts of ozone.  So id avoid In HVAC myself, but I do use daily in my main purifier unit.  White Hepa grade filters most important will capture particles, viruses etc.  That's the main thing.   Good units for VOCs/odors are 1,000 dollar IQ AIr and 750 dollar Austin Air.  Among others.  But those don't move a lot of air, slower better for the carbon pellets to absorb odors.  So best to pair with other units that move more air with HEPA. Lots of good brands there like Winnix, Levoit, and Coway, that all perform well, have various sizes, features etc.  

I have a big purifier right next to my computer myself. (but not because of dust but more so because I have 8x purifiers in a 1 bedroom apartment so that happened to be the best spot for it.) So as others said you dont really need to put a purifier there, although it is more useufl to be near you. But also does not need to be. But next to a computer is an OK place, esp if you are using the computer a lot. But fine anywhere in the room thats gets good airflow. As per units Winix + Levoit are both excellent, however they are not known for being quiet per se. I find my Levoit quiet, and Winix scores about the same in decibel testing. However "quiet is subjective to the user, so you can always run them on low if needed. Thing is, if you run it on low you you are losing a bunch of the CFM effectiveness, so I suggest trying to run high and see if you adjust to minor noise. As CFM ratings are based on it running on high speed. (I got accustomed to the mild noise and now its a nice background noise....that I don't even notice.) Or at least run it on high when not in the room, or try to adjust over time, as you get more out of it the more/higher you run it. But certainly on low most units wont make much noise. My Levoits to me are not loud even on high. (Winix should be same.) I would not get a Xiaomi over Winix or Levoit, as I am not that familiar with Xiaomi, although those might be OK too. I do know that Winix + Levoit are both great. So either of those should be fine. Levoits dont have ionizer unless it says Plasma Pro. Some Winix I think might have it, but idk which models as I dont have Winix myself. (You also dont need ionization but if you get additional units you can always try out one of of those, just make sure you can toggle it on/off in case you dont like it.) But you should be fine with any Winix or Levoit.

I would not buy a Xiomi over a Winix unless there was a substantial price difference. (as in almost for free.) As I think it is a brand with less quality, so the units may break more frequently. As well they seem to discontinue units and then people can't find filters to even use them. Thus why they are cheap. The units I have had the most problems with...with units breaking within 6 months to 1 year...are cheap random brands. (they often usually only have a 1 year warranty.) I would strongly recommend Winnix or Levoit, as those are good quality, you wont be able to not find a filter etc. and they perform the best in recent testing. Here is a recent thread on people saying not to buy Xiaomi. [https://www.reddit.com/r/AirPurifiers/comments/1mgg0bo/do\_not\_buy\_xiaomi\_air\_purifiers/](https://www.reddit.com/r/AirPurifiers/comments/1mgg0bo/do_not_buy_xiaomi_air_purifiers/)

For smoke you need the black carbon strips that bind to the carbon in smoke, so you don't breathe them.  And carbon pellets/activated charcoal that absorb smoke + odors in the air.  The normal white Hepa material is excellent for particulates in the air, but does 0 for smoke + odors.   Some purifiers will have a thin strip of carbon, and maybe even a few pellets, but at the low price range it's not much/would only help a little.  So the most cost effective thing....is probably a ventilator with carbon filter, such as that weed growers use.  AC Infinity makes a line of them and a set of both costs around 120-160.  https://www.amazon.com/AC-Infinity-Filtration-Ventilation-Hydroponics/dp/B09NXKGK89 Another affordable idea is a corsi Rosenthal box, but with carbon filters.  Air Fanta Pro sells their unit with carbon filter for about 15 bucks more (180 I think.). So you might want both that + a ventilator with carbon filter. You can also just buy packs of carbon strips for like 15 bucks...and place around your space, especially around doorways some places where air might seep or where air flow.  Or put one behind a fan..and now you have a DIY carbon filter essentially.   Most typical air purifier units are geared towards particulates, so you would be paying a lot, to get only very little carbon effect.  With most units under 200 bucks or so.  Good units for smoke + VOC would be like an Austin Air which is 750.  IQ Air great but like 1,000 dollars.  Mid-range would be Alen which has different sizes like 250-400 range I think.  But a vebtialtor with carbon filter will be far cheaper and probably more effective for smoke + odors.  Likewise CR box.    A good affordable brand in general is Levoit,and they do have a little carbon in their filters usually...but they can only help a little.  You will need much more than what normal air purifiers can give....unless you have like 10 or 15 or 20 air purifiers each with carbon strip + pellets maybe.  So most cost effective by far...are the other options.  

I personally hate round purifiers since they typically have built in pre filters that you cannot vacuum. That’s why I really prefer Coway (except the 350 and 450 same reason no separate pre filters) as without a separate pre filter you can clean you’ll be changing your filters twice as often. The levoit 600 is otherwise a great purifier. Levoit does have a pre filter but it’s harder to clean imo. The 1512 is a screen you pop off and take a vacuum too with really easy access

With the 1512 for example the HEPA filter is what catches that, not the odor filter or the pre filter. You can vacuum the pre filter with no worries, only things that will be on that is hair lint and dust :)

Air purifiers work remarkably well.  We have a cat and dog and I sometimes suffer a bit with cat hair giving me a persistent sickly cough. I bought a small Levoit air purifier for the bedroom and was amazed at how much better I slept at night. I ended up buying a larger whole house air purifier, (same brand). On a normal setting they run silently and barely use any energy. Not sure about other brands but the Levoit purifiers have reusable filters which you just take out and vacuum clean every week or so.  I'd buy one if the single room air purifiers and see if it makes a difference. As far as visiting other people's homes, there's not much you can do about it.

True HEPA is not necessary for good performance. You can look into how a CR Box works and it just uses regular furnace filters. Levoit purifiers perform well in independent testing. They shouldn’t have been advertising HEPA filters when they weren’t technically HEPA, but they are still high quality filters. The biggest mistake people make is not buying one large enough for their space, which is why people complain they “don’t work”. You bought a big purifier for a big space, so it’s appropriately sized and is working to clean your air. I’d run it on a higher setting overnight though. At least level 2 if noise is a consideration. A good rule of thumb is just to pick the highest level you can deal with noise-wise and leave it there.

There’s no need to get a new purifier just to have a HEPA filter. I would stick with the Levoit.

Levoit is quieter. People get a little hung up on the no HEPA thing and I get it, but these filters still preform really well like you said. You are probably looking at a filter change every 4 months to keep the allergens down. So just take a look at the replacement costs for three filter changes a year. I think both of those units probably have cheaper aftermarket filters available. There’s no reason to avoid Levoit unless you hate the look or really want a HEPA filter. I will say that while the purifiers will help, they’re not going to solve being allergic to a cat and owning one. You also need a good bagged HEPA vacuum and probably some ongoing antihistamines. Anything the cat sits on needs to be dusted/vacuumed super regularly. Good luck. I love cats, but am very allergic too. Hope you can find some solutions that work for you.

Please read the stickied thread in the sub about dust. Dust is not pm2.5. You also should be running the purifier on the highest setting you can stand noise-wise. Put it there and leave it there. No eco or auto mode. Also, you need multiple purifiers to clean the air in that amount of space. It doesn’t matter that the rooms are open to each other unfortunately. The square footage advertised by all of the manufacturers is for one air change per hour, but to really clean your air, you need 4-6 air changes per hour. That means roughly the Core 600 is good for like 300ish square feet only. There are other stickied tools on this sub to explain or you can read about it on [House Fresh](https://housefresh.com/cadr-calculator/) which is a trusted resource Just to give you an idea, I run a Core 600 in my living room and then have three other vital 200 units on my first floor (kitchen, dining, and office). They are all open to each other, but that’s the number of units I needed to get the required coverage. Air doesn’t move effectively through openings or around corners or partial walls. My core consistently reads 001 which matches the other separate monitors I have to make sure everything is working correctly.

Please see the stickied thread in this sub about dust. Purifiers are not designed to get rid of dust. Shark sucks. Don’t under any circumstances buy one. BlueAir is fine, but overpriced and the filters are expensive. Levoit is a good, cost effective brand. It is on par with Coway and Winix. You cannot go wrong with a unit from any of those manufacturers.

You are going to need to calculate the CADR needed for each room/area of the house (ie even if the living room and dining room are connected, each needs a purifier if possible). You can use [this calculator](https://housefresh.com/cadr-calculator/) to figure out the CADR. I will save you some time though and tell you the only purifiers close to that budget are going to be from Levoit. They are good machines and come in a variety of sizes. They are not fancy, but get the job done.