GCX MultiGas XE

Thanks for the great tips! The Airpura C700 DLX does look interesting. My biggest problem with Airpura is a complete void of reviews or testing. Do you have any direct experience with them by chance? I'm leaning heavily IQAir mostly bc there's more reviews and they are mostly positive. I know VOC's are hard and expensive to measure but I'm shocked almost no online reviews even do basic VOC tests using airthings or other sensors. I plan to post my 30 day airthings VOC chart before and after I purchase an air purifier to show some sort of evidence if it does anything. Looking at this chart for my levoit, it's very clear that it's great for PM but useless for VOC's. I would think the internet would be covered in tests like this but there is near zero data out there. This makes me very suspicious that trying to combat VOC's is a hopeless marketing scheme to upsell expensive carbon filters. Any company that showed off real world results would have a huge advantage, but none do which makes me think VOC capture is not practical. I do run a dehumidifier in my room every night and average 37% humidity which helps with the musty smell. Whenever I'm away on vacation and don't run it the smell comes back. Unfortunately can't get the landlord to do anything about it.

I got the small r414 I think is the model. So far I haven't been able to detect any impact on VOCs. In fact I'm currently testing if it's making my VOCs significantly worse or not on my air things. I much prefer my levoit Everest air for PM. For VOCs that does nothing, but as far as I can tell neither does the Airpura. I'm probably going to try an IQAir instead of a bigger Airpura next, you might want to consider that one.

For reasonable VOC removal there are only 4 players I know in the market which offer products which have the minimum 10 pounds of sorbent media: Airpura, Allerair, Austin, IQAir. Wildfires product a huge mix of chemicals - from the vegetation, contents of burned buildings, etc. There is no consumer solution that removes all VOCs. Each type of media is better at some chemicals, not so good or not effective at all with others. For the same reason there is no sensor that I know that will give you the level of all VOCs. These machines and filters tend to be expensive. I just upgraded my Austin units with Immunity Machine filters which cost \~$700 each. We were spared wildfire smoke this season but with AQI numbers breaking 100 I was able to keep my indoor values close to 0. I use Austin and IQAir VOC machines along with Honeywell and Whirlpool HEPA units, 3 filters per room.

I have Austins and IQAir MuliGas. The Austins were recommended by a clinic which treats individuals with extreme chemical sensitivities. You want a unit where the fan feeds the filters (1st in the chain) to avoid contamination from the fan itself. No filter is going to eliminate all VOCs.

I have a couple of models: Immunity Machine, Healthmate Plus, bedroom machine. There have been some reviews stating that Austins are slower at clearing a room of particulates. My main concern is VOCs and since I run 3-4 filters in each room that isn't a concern for me. Am now testing the immunity machine. Seems to do a much better job with VOCs, although final results will take a while. What is your concern with IQAair?

I use Austin Immunity machine and iQair GC Multigas units as VOCs are a major concern for me. Not rated.

I run 3 filters, Austin and IQAIR, in each of 2 spaces - one 300 square feet the other 600 square feet. If the air is poor outside my Purple Air sensors will still show green. However there are so many chemicals in wildfire smoke, particularly if structures have burned, that they don't get everything. I am sensitive to terpenes and right now they don't help with the Camphor tree flowers. So they can greatly improve air quality but don't expect all VOCs to be removed from the air.

For best VOC removal, such as mycotoxins, you need a lot of absorbent media. Checkout Airpura, Allerair, Austin, IQAir. All are in the $1k range. I'm unsure whether any filter will eliminate mold sensitivities. Did see an improvement when upgraded my Austins with Immunity Machine filters but molds still aren't totally controlled. There are clinics which can treat mycotoxin sensitivities. Can be quite expensive.

Running both IQAir and Austin Immunity Machines in my major rooms particulates run from 0 to under 10.

I have had my Austin, IQAir, Honeywell and Whirlpool machines for as much as \~20 years and have had no problems with filter replacements.

The 4 vendors with the best VOC filters are Airpura, Allerair, Austin, IQAir. Absorbent media composition and weight vary by manufacturer. IQAir has models that go up to 32 pounds of media, at least according to google search. Note that no VOC filter will remove all VOCs. They do well with some chemicals, partially control some, and totally ignore others. I use IQAirs and Austin Immunity Machines, multiple units per room unless you want to put up with the noise running the fans on high speed. Had a room repainted and requested a low VOC paint. Was pleasantly surprised that I had no problems with the paint even though I am extremely chemically sensitive. It is possible that the renovations don't cause a VOC problem at all, or maybe just for a few days.

My Austin, IQAir, Honeywell and Whirlpool filters all work with smart plugs. When you purchase make sure you can return if it doesn't work as features change over time.

Hey, you and I are in the same boat. I had a baby boy at 31 weeks, now almost 5 month adjusted, and I went down the air quality rabbit hole hard. I want to do whatever I can to keep him healthy and developing normally. He sleeps with us in our room right now. I have a clean air kits luggable xl pc fan cr box and a IQair Health Pro Plus running on setting 2. Both run 24/7. This gives me a lot of air changes per hour and some gas filtration, while staying below 50 decibels. In the rest of the house, I have more luggable xls, smart air blast, iqair gc and GCX, Coway 400 and 300, and an Alen 25i. I think it’s important to get a standalone air quality monitor like the air gradient one or purple air zen. I run the hvac blower fan 24/7 to circulate air through the house. I also open windows every morning and bring in fresh air to keep CO2 low. I don’t know what your budget is, but you can make your own cr boxes for really cheap and then throw a few nice hepa air purifiers on top. I bought all the expensive units used (iqair, Coway, smart air) and saved a ton of money. Just gave them a good cleaning and new filters. Another important thing is to always run your kitchen hood vent when cooking I’ve been keeping my house between 68-72 degrees Fahrenheit so that he sleeps his best and relative humidity between 45-55%. I have a Midea Cube dehumidifier I run when it’s really humid out and humidity in the house gets above 60%. I also vaccum and mop the floors all the time now. We have an old dog that sheds a lot and the floors get covered in hair if I don’t stay on top of it. I kindof rambled but that’s just been what I have been doing and what purifiers I bought to give you some ideas and things to look into.

I just got an Alen Air 25i for my little office and it’s been a really great unit for the last few weeks. Alen sells bundle “whole house” solutions that might work for you. For me, I put a smart air blast in my living room, a iqair GCX in my kitchen, iqair gc in my dining room/front foyer, Alen 25i in the office, Coway Air Mega 300 and 400s in our spare bedrooms, an iq air health pro plus in the master bedroom, and 4 clean air luggable cr boxes spread out throughout the house. Do I have an addiction to buying air purifiers? Yes. Very weird addiction. But all were bought off Facebook marketplace and were pennies on the dollar compared to new. Just had to give them a good wipe down and put in a new filter.

Hey, you and I are in the same boat. I had a baby boy at 31 weeks, now almost 5 month adjusted, and I went down the air quality rabbit hole hard. I want to do whatever I can to keep him healthy and developing normally. He sleeps with us in our room right now. I have a clean air kits luggable xl pc fan cr box and a IQair Health Pro Plus running on setting 2. Both run 24/7. This gives me a lot of air changes per hour and some gas filtration, while staying below 50 decibels. In the rest of the house, I have more luggable xls, smart air blast, iqair gc and GCX, Coway 400 and 300, and an Alen 25i. I think it’s important to get a standalone air quality monitor like the air gradient one or purple air zen. I run the hvac blower fan 24/7 to circulate air through the house. I also open windows every morning and bring in fresh air to keep CO2 low. I don’t know what your budget is, but you can make your own cr boxes for really cheap and then throw a few nice hepa air purifiers on top. I bought all the expensive units used (iqair, Coway, smart air) and saved a ton of money. Just gave them a good cleaning and new filters. Another important thing is to always run your kitchen hood vent when cooking I’ve been keeping my house between 68-72 degrees Fahrenheit so that he sleeps his best and relative humidity between 45-55%. I have a Midea Cube dehumidifier I run when it’s really humid out and humidity in the house gets above 60%. I also vaccum and mop the floors all the time now. We have an old dog that sheds a lot and the floors get covered in hair if I don’t stay on top of it. I kindof rambled but that’s just been what I have been doing and what purifiers I bought to give you some ideas and things to look into.

I just got an Alen Air 25i for my little office and it’s been a really great unit for the last few weeks. Alen sells bundle “whole house” solutions that might work for you. For me, I put a smart air blast in my living room, a iqair GCX in my kitchen, iqair gc in my dining room/front foyer, Alen 25i in the office, Coway Air Mega 300 and 400s in our spare bedrooms, an iq air health pro plus in the master bedroom, and 4 clean air luggable cr boxes spread out throughout the house. Do I have an addiction to buying air purifiers? Yes. Very weird addiction. But all were bought off Facebook marketplace and were pennies on the dollar compared to new. Just had to give them a good wipe down and put in a new filter.

Iqair is a great option. Have one in our bedroom with our 5 month old baby. But can only run it on setting 2 (75 cfm) without going above 50 db. We also have a luggable xl cr box in the bedroom to get more filtration without increasing the sound in the room. We have a Smart Air Blast in the living room and it’s a a quiet beast. Pushes a ton of air, however it’s power hungry. I’m also a fan of the Alens for how they sound and Coway AirMegas.

Both the IQAir GCX and GC series use a pre-filter that's EN 1822-1:2019 Efficient Particulate Air (EPA) E11. IQAir calls this "H11", but it is really EPA E11. Both the GCX and GC are meant for gaseous removal, so it makes sense to use EPA E11. This prevents excessive pressure drop. The IQAir GCX MultiGas is very good for gaseous removal, although it's expensive compared to heavyweight sorbent media purifier brands like Airpura (max 26 lbs. carbon canister) and AllerAir (max 34 lbs. carbon canister). However, I'm quite certain the GCX MultiGas pre-filter has far more surface area compared to mechanical filters present in comparable Airpura and AllerAir models. Do you have elevated levels of gases/vapors/odors (includes VOCs)? I would recommend having air testing performed with Gas Chromatography-Mass Spectrometry (GC-MS) analysis *first* to determine the gaseous species in your airspace.

AirDoctor doesn't have much activated carbon in their filters... definitely not thick. You're right about IQAir, specifically the GC series purifiers. AllerAir and Airpura purifiers tend to have heavier carbon/sorbent media canisters for the money.

Most common air purifier brands do not have enough nor the right type of sorbent media for gases, vapors, or odors. Sorbent media in air purification = activated carbon, activated alumina, or synthetic zeolites. Heavyweight sorbent media purifiers are very expensive, very loud, and clean the air more slowly than particulates-focused units. This is due to the need for ["dwell time"/"residence time"](https://www.airscience.com/carbon-filters) and the thick media beds. The two major heavyweight brands in the USA & Canada are **Airpura** or **AllerAir**. You want to look for models with 15 lbs.+ carbon canisters. Most standard options for these purifiers are plain/chemically untreated sorbents, which do *not* have high removal capacities for all gaseous "species". This sometimes presents problems where an odor emanates from the sorbent bed (possibly the not-well-adsorbed acetaldehyde) or there's a spike on tVOC monitors despite a reduction in odors. Assuming you don't live near a refinery or have really bad air chemistry otherwise (e.g., from fires), you may want to look into potassium permanganate (KMnO₄) impregnated activated carbon from Airpura or AllerAir. You'd have to contact the respective company first to specify this. KMnO₄ works in part via redox (reduction oxidation) reactions by breaking down certain gases. This can be problematic in unknown and/or highly complex air chemistries where resulting gases may be problematic. It can also off gas as it saturates or loses efficacy.

Your best options are likely the IQAir GC or GCX series purifiers. As for the exact model, you may want to choose one with potassium permanganate (KMnO₄) impregnated carbon or alumina. See [my other comment in this thread](https://www.reddit.com/r/AirPurifiers/comments/1oco7i5/comment/nkoz4yw/).

I would add IQAir to this, especially the Multigas GCX (emphasis on X, it's superior to the GC which is already a great unit.) Oransi has a standalone carbon model as well. But yeah this list including your comment is very complete. I spent months researching and created a comprehensive brand list and narrowed it down to the exact same brands you mentioned for actual decent VOC filtration. Real world performance is a different issue however and the one thing I would emphasize to OP is that 2,000 is a *lot* of square footage and these types of purifiers are very expensive and if you're looking to consistently purify the entire dwelling then you'd need at least a half dozen 250CFM units to make a difference. It will be expensive and loud and the filters will saturate and need replacement very often if you have a smoker nearby.

If money is out of the question. IQ Air Multigas.

Iq air MCS hands down. Entertain no other option, its ability to filter is down to the smallest size I can find.

You’re right, my bad. Guess is a colloquial name we’ve given it in my house. I’ve had two for 9 years and can’t imagine life without them. We do vacuum the bottom pre filter every two weeks to prevent dog hair from reducing flow. I do bring a medium sized new version Air Oasis when traveling.

IQ Air multi gas. My doctors offices, pulmonologist, cardiologist, etc . uses them. It really helps me breathe at home.

Unfortunately the most effective purifiers are not cheap. I bought an AirDoctor because the IQAir was too expensive. It didn’t seem to do anything, so I ended up selling it and buying the IQAir in the end. The IQAir MultiGas was most effective (of the IQAir lineup) against VOCs like mycotoxins last I looked. I supplement with Microbalance EC3 candles

I agree with the above comments. I am extremely chemically sensitive and my condition started in an office where we brought in a lot of IKEA MDF tables. We returned the tables, but my condition remained. I recommend the IQair Multigas if you want the best home machine for removing formaldehyde and VOCs. It’s expensive though. For basic filtration at a much lower cost, I’d go with Winix. We have the pet one and it’s actually amazing at eliminating smells in the kitty litter room. Replacement filters are also not too expensive. To solve the CO2 issue, you have to exchange indoor air for outdoor air. Purifiers don’t remove CO2 and create fresh Oxygen. Trees do and for trees/plants to work sufficiently indoors hid need them almost wall to wall (there are a lot of myths about like you only need one spider plant etc. but you’d actually need to live in a greenhouse of plants). For CO2 you’ll need to open windows or vent. However, when you use a vent, like a bathroom fan, you’ll likely be pulling replacement air from someplace else in the building, not necessarily a better place with fresher air. A fan blowing in pulling fresh outside air in can get a lot font in a short time. Even ten mins can make a big difference. Go search on YouTube for air purifier info. There is a lot of expertise out there. I learned about the IQair/Winix combo from a researcher in Beijing. Using both makes the IQair filters last longer. Also avoid Levoit. They just got caught lying about being hepa in several of their models. They do have good air purifiers, but some are apparently crap. Last note: because all air purifiers are noisy when they are on high, it’s better to get one that’s for a much larger space and run it at a lower, quieter speed. Consider getting two Winix purifiers or 2 of some other kind with some carbon in the filters. Winix is at Costco.