AtmostAir System
I need your help. I’m designing a 9k Sq.Ft. house in TX, and the homeowner is very high into IAQ, as their kids have respiratory issues. The HVAC contractor that services their current house is recommending using an AtmosAir system. Their website has some amazing claims. I know nothing about it. I don’t know if it’s the greatest thing since sliced bread or snake oil. See: https://www.atmosair.com/residential-systems
I expect this house to have a low HERS 40ish and 1ACH50. Conditioned attic with units and ducts in it, and some ducts thru chases in the floor trusses, so the entire HVAC system will be inside CS. I’m thinking we’ll end up using 3-2 ton ac units, all high-efficient heat-pumps.
Has anyone of you used this system or anything similar? If this was your house, would you use this system or similar? I appreciate any input.
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Having tried it, I can verify that negative ions cause air born particles to stick to things. But not clear to me that it wouldn't be better to just use conventional filtration.
Do be clear about what you want to remove from the air - VOCs, PM2.5, radon, CO2, etc.
Thanks Jon. Since Covid, I've been requesting of the HVAC contractors to increase MERV11 filters to MERV13, and MERV16 as an option. We expect to use low-voc, no formaldehyde, no gas FP, I think the owner has been moving to induction cooktop, and the usual primary targets for a good house IAQ, , ozone, etc. I believe with a tight building envelope, urban air pollution is minimized.
Ions give a static charge to particulates that tends to make those things clump together and bind to other things. The only thing that jumps out at me from that site is the claim that their device makes "positive AND negative ions" (my emphasis). Normally you'd have negative ions only. With postitive and negative together, I'd expect charge cancelation and limited effectiveness. I would want to do a test with a small one of these units before comitting to a large-scale installation.
I would recommend you consider something I have done many times in datacenter facilities that are operated as clean rooms. We run slight postive pressure ALL the time, by bringing in outside air through a dedicated conditioning unit (mainly for dehumidification), and a combination pleated and bag filter. This keeps a constant slight positive pressure for the enclosed space, and that positive pressure is maintained with well-filtered and conditioned air to ensure nothing can leak INTO the enclosed space -- all the leaks go OUT. This lets you control what can get in, making it easier to keep the enclosed space clean.
I would stay away from any natural fiber products (wool carpet, etc.), since those are a source of dust/particulates. Synthetic fibers are much less of a problem in this regard since they are long polymer chains that don't shed bits of themselves. Paper products are another issue. Most dust in clean room facilities comes from cardboard packaging and shed human skin cells, for example.
I'd consider activated carbon filter inserts in addition to your high MERV filters. Activated carbon can trap a lot of chemical compounds and other stuff too small to get caught in conventional filters. Electrostatic filters can help with allergens, but many people don't clean them enough for maximum effectiveness, and they work the opposite of normal filters in that they perform worse as they get dirtier.
It might be worth contacting a respirtory specialist, especially one that is familiar with your customer's family, to find out any specific sensitivities their children have. If you know certain specific things that are issues, then you can be extra sure to avoid using any products that might cause problems.
I wouldn't rely on that ion device as a primary means of filtration. I would only use it to supplement other conventional filters if at all.
Bill
Thanks Bill, for your detailed information. For the last few years we been using ERV’s to provide balanced ventilation and IAQ systems to control temperature and humidity. I will take a look at carbon filters, thanks. I’ve never been a fan of Electrostatic filters, so I don’t think they come into the equation, but I don't have the last word.
I’m pretty sure their kids are under medical observation for the respiratory issues, and I once, asked the homeowner whether their kids had seen a specialist for a sensitivity test and picking specific products or chemicals harmful to them, but that was awhile back, and I can’t remember what they said. I’ll bring it up again. In fact, she came to a presentation I made about ZER and healthy homes a couple of years back, and that was one of the main reasons they hired me. I'll keep digging into this .
I would definitely press the “talk to their specialist” issue. If they’re trying to address their kids IAQ needs, then it’s worth making sure whatever you do is targeting the things that are the biggest issues to their kids.
BTW, pretty cool you got a project specifically to address air quality issues for sensitive kids. You might try talking to some pediatric hospitals that deal with kids with unusual sensitivities. There could be some more buisness out there for you as a builder familiar with these specialties, and you’d get to help out some kids in need too — a win-win :-)
Bill
I got indoctrinated to healthy houses about 20 years ago in NM and CA, for a clients with highly developed chemical sensitivities. So far, over the years, all my clients with those issues love their houses.
I don't think my TX client's kids have chemical sensitivity, I think is more respiratory, like asthma.
I'm sorry, but it seems everyone here is being far too gentle. At best, this is snake oil. At worst, it's another ozone machine scam. As Jon mentioned at the top, ionizing air can cause increased deposition of particulate pollution onto surfaces, and this does help to clean the air. The best example of reasonably well-designed equipment for this purpose is the traditional electrostatic air cleaner. When kept clean, they are very effective, but as also discussed above, nobody maintains them properly, so they don't do much of anything in most houses.
But that's not what the AtmosAir claims to do. The manufacturer claims that the "positive and negative ions" (of what?) magically seek out pollution and neutralize it in place. And that includes everything from gases to particulates to viruses to anything else that might be objectionable in your air. They don't tell us what is being ionized or anything about how those ions react chemically with anything in the air, not to mention everything in the air. Their video uses the old ozone machine trope about the "fresh" air near a waterfall or after a thunderstorm. That's ozone salesman codespeak and automatically raises a big red flag in my book.
Thanks for your point of view, Peter. I also don't believe in ozone creating machines, and as I said above, their claims appear to be too good to be true. I knew I could count on some of you guys, here at GBA, to get an unbiased opinion.
Thank y'all.
Peter has it right. A common (and pretty much insurmountable) issue with all ionization systems is that some amount of ozone is going to be created. Ozone is itself a pollutant with known negative human health effects.
While ionized air can make it easier to get rid of particulate matter, can kill some (but not all) pathogens and break down some (but not all) volatile organic gases, it's not going to neutralize or remove other indoor air quality problems.
My personal preferences for addressing indoor air quality are increased ventilation rates (with energy or heat recovery) combined with MERV 13 or higher filtration, and LOW duct velocity on HVAC systems, especially low velocity at the filter(s). The effectiveness of filters at taking out particulate matter (even PM2.5) decreases with air velocity. The static pressure also decreases with velocity, so oversizing the ducts and filters for the target cfm works in favor of both indoor air quality and lower air handler power.
In the zone 2A & 3A parts of Texas it goes without saying that a tight high-performance house will need mechanical dehumidification independent of the air conditioning system to manage indoor humidity levels, which will directly affect indoor mold levels. The higher the ventilation rate, the more dehumidification would be needed, of course.
Dana, thanks for your input. I feel confident that the original plan still works best, as is pretty much as you and others described. It’s hard to avoid salesman’s claims to muddy the water on so many issues, especially nowadays, in this Covid year, where our nerves are on heighten alert.