Cold Plasma Air Purification

[Frank10]

I am no expert, but... the supply side, I thought was between the handler and the vents leading to the registers. I would move the UVC lamp... and make sure that it is UVC... to the return side (where the air hitting the slab comes from) and protect any plastic or wires the light hits. It must be UVC... It is supposed to keep stuff from growing there.

I read the instructions for the Phenomenal aire and they actually recommend the return side as well...

This sounds very discouraging. Make sure you are running long cycles if possible (with multi stages is should be...)and not short ones. which would also keep down the humidity.

Are you bringing in outside air?

Kevin,
Thanks for the reply.

Unfortunately, I can't move the UV-C lamp to the return side without cooking the media filter. (The media filter is directly above the coil, which is where we want it.) Previously, we had the Phenomenal Aire installed on the older system Lennox on the return side, after the filter but before the coils, but we didn't notice any difference in the air quality--this after a year of running it there. Maybe it helped keep growth off the coils, maybe not. We've considered bringing the Phenomenal Air back up to the return side, but I hate to put a hole in this new Carrier unit if the Phenomenal Aire isn't doing anything.
(The iWave bipolar ionizer can be magnetically mounted inside the cabinet, but at this stage, I'm not sold on this application of the needlepoint bipolar ionization technology.)

The 5-stage Carrier does run long cycles and often stays at the first stage with a very low fan speed. I often don't even realize it's running. (This was a selling point for us. The Lennox short cycled in cooling.)

We keep the indoor humidity at around 50% RH. Our crawlspace is encapsulated and has a Sante Fe dehumidifier where we keep the RH around 45%. Ducts, with the exception of the first 10-15 feet of the trunk line, are not insulated. The foundation walls are insulated with 3" fiberboard. The supply lines from the trunk line are all new hard pipe that I installed. (Fun times doing that.)

The only outside air intake is from opening windows, which we haven't been doing much of because it's hot and humid right now in Virginia. (I still crack a window in the morning or if we're using a clothing dryer or a bathroom fan.) My next step it to open up the trunk line and manually clean some of the stuck-on dirt, that or replace it. By the way, Ductmate makes some nice pancake-type access doors if anyone is considering cutting holes in their ductwork.

I never thought I'd spend so much time trying to get clean, cool air in my house.

Thanks again for your reply.

Frank

[Kevinyork]

Kevin,
Thanks for the reply.

Unfortunately, I can't move the UV-C lamp to the return side without cooking the media filter.
Previously, we had the Phenomenal Aire installed on the older system Lennox on the return side, after the filter but before the coils, but we didn't notice any difference in the air quality--this after a year of running it there. Maybe it helped keep growth off the coils, maybe not.
(The iWave bipolar ionizer can be magnetically mounted inside the cabinet, but at this stage, I'm not sold on this application of the needlepoint bipolar ionization technology.)

The 5-stage Carrier does run long cycles and often stays at the first stage with a very low fan speed. I often don't even realize it's running. (This was a selling point for us. The Lennox short cycled in cooling.)

Frank

It is discouraging that you did not notice any less growth on the coils with the phenomenal aire! and I thought the i-wave was basically the same exact thing... except you could mount it right on the fan magnetically where the intake opening is.

We just ordered a 2 stage condenser with a variable speed handler in the hopes of controlling humidity with out a dehumidifier. We are only 1100 sq ft.

I am concerned about lung issues being exacerbated with the phenomenal aire. I also have a super human sense of smell and chemical sensitivity... which is also an Achilles heel.

[Frank10]

Hey, Kevin.

We never actually saw any growth on the coils of the Lennox indoor unit. We had them cleaned several times by HVAC techs and I cleaned them several times with ProGreen (Diversitech) and later with DirtySox spray. (The coils were shiny, but the issue must have resided between the fins because it quickly returned.)

In the winter, when the unit kicked into the defrost mode, the entire house filled with a latex paint odor. This hasn't been an issue with the new Carrier unit, so, fingers crossed.

I'd prefer to rely on fresh air and low RH over UV-C and bipolar ionization. Maybe cleaning the coils every 6 months with a mild coil cleaner is a good way to go.

Good luck maintaining your home air quality.

Frank

[IndoorAirNerd]

I'd prefer to rely on fresh air and low RH over UV-C and bipolar ionization. Maybe cleaning the coils every 6 months with a mild coil cleaner is a good way to go. Frank

Having mechanical outdoor air ventilation (meeting ASHRAE Standard 62.2) and a good media filter (say MERV 11+) goes a long way. The problem with air cleaners using ionization (e.g. bipolar ionization, cold plasma, corona discharge) is that they create reactive oxygen species (ROS), which includes ozone and other chemicals. Do ROSs break down VOCs and kill microorganisms? Yes, at the right concentration. But reactive oxygen species also have a deleterious/harmful effect on humans.

There is very little peer-reviewed research not funded by manufacturers published in reputable journals. Also the ROS reactions are complex. Until it all gets sorted out by academia, I prefer to recommend outdoor air ventilation and high-efficiency media filters rather than ionizers.

[Frank10]

Having mechanical outdoor air ventilation (meeting ASHRAE Standard 62.2) and a good media filter (say MERV 11+) goes a long way. The problem with air cleaners using ionization (e.g. bipolar ionization, cold plasma, corona discharge) is that they create reactive oxygen species (ROS), which includes ozone and other chemicals. Do ROSs break down VOCs and kill microorganisms? Yes, at the right concentration. But reactive oxygen species also have a deleterious/harmful effect on humans.

There is very little peer-reviewed research not funded by manufacturers published in reputable journals. Also the ROS reactions are complex. Until it all gets sorted out by academia, I prefer to recommend outdoor air ventilation and high-efficiency media filters rather than ionizers.

Thanks for the post. ROSs and limited peer-reviewed research are a concern.

I wonder if anyone has hooked up a damper on a fresh air intake and tied that in with an outdoor air quality sensor. (Neighborhood meat smokers, fire pits, and fireplaces often make our outside air, well, smoky.) It also might be useful to limit air intake on excessively humid days.

Thanks again for the post.

Frank

[randyf]

Having mechanical outdoor air ventilation (meeting ASHRAE Standard 62.2) and a good media filter (say MERV 11+) goes a long way. The problem with air cleaners using ionization (e.g. bipolar ionization, cold plasma, corona discharge) is that they create reactive oxygen species (ROS), which includes ozone and other chemicals. Do ROSs break down VOCs and kill microorganisms? Yes, at the right concentration. But reactive oxygen species also have a deleterious/harmful effect on humans.

There is very little peer-reviewed research not funded by manufacturers published in reputable journals. Also the ROS reactions are complex. Until it all gets sorted out by academia, I prefer to recommend outdoor air ventilation and high-efficiency media filters rather than ionizers.

This is very dependent on the oxidant in question.

Hydroxyls - the most potent oxidizer (other than fluorine) - as regards VOCs are harmless. The FDA and lab data both agree on this. These critters have a life span under a second. Most won't survive very far from the device that's generating them.

Ozone - a second rate oxidizer - can be deleterious but at concentrations much higher than what *most* indoor devices output.
NIOSH and OSHA have a limit of exposure 100ppb for 8 hours 5 days a week for a life time. Most devices, not all, output under 10 ppb.
Ozone levels is my home town is currently about 40ppb.

Hydrogen Peroxide species that some devices(RGF) claim to generate can be harmful but at levels much higher than these these device generate.

As an aside I don't believe that neddle point bipolar devices (GPS, Phenom Air, Nu Calgon) produces Any oxidants. Not sure if the manufactures are lying or just confused but I'm very very doubtful these devices have any effectiveness for reducing VOC levels. GPS - if you're listening - I'd like to hear your input.

What is under appreciated is that VOCs, unlike say CO2, boil at temperatures much higher than ambient. What gets into the air are molecules that "off gas".
Until the liquid/solid source of these VOCs are eliminated there will be a problem.

[randyf]

I would like to add that partial breakdown products of oxidants can be harmful. The data is mixed on this warning.
Also if these breakdown products are a problem steps might be undertaken to avoid or minimize the issue.

[randyf]

Thanks for the AlphaLab link, Randy.

A little searching and I see that Phenomenal Aire also sells a duct-mounted ion meter under its commercial product. (I can't post a link due to forum restrictions, but it's under the commercial section of their website.

I wonder if this built with GPS guts from the link RJK provided.

My wife is out of the house so I’m running the heat mode and fan on continuous trying to burn off any dust on the heat strip and set free anything that might have grown on the 2-month-old evap coil during cooling. Phenomenal Aire is on. Dylos showed particle counts low and falling until I opened the windows. (A neighbor has a fireplace or firepit going.) No odor when only the fan is running, but under heating (strip or coil) there is some dusty odor. This isn’t the first run of the season, so I’m a little disappointed that there is still an odor.

I'm temped to clean the evap coil with Pro-Green (Diversitech), but at 2 months in it seems overkill...unless the coils were warehoused in cave prior to installation.

Frank

Hey Frank,

i know this is a couple of year old, but I was speaking to Alpha Labs the other day and they mentioned they build the ion meters for GPS. They just label for GPS.
Thought you might be interested.

[Frank10]

Thanks for the info, Randy.

https://www.alphalabinc.com/product/aic/
$528.00
Looks like the Air Ion Counter is available in three ranges:
Max range 2 million ions/cc
Max range 20 million ions/cc
Max range 200 million ions/cc

From Alpha Labs website:
"The 2 million range is sufficient for almost all situations except for measuring very close to electric ionizers or strong radioactive sources. For these applications, models with ranges of 20 million and 200 million ions/cc are also available."

I think I'll pass along this info to my HVAC company and see if they bite.

I pulled the fuse out of the Phenomenal Aire yesterday and we're running the HVAC without it for an experiment.

Frank

[randyf]

Hi Frank,

I'm really at my wits in dealing with overstated, under supported claims of various manufacturers regarding IAQ, especially with VOCs.[/B][/I]

I don't think GPS systems emit harmful oxidants (they've demonstrated that on their youtube channle), but I also don't think they are effective in reducing VOCs.
That's not to say they might be effective in reducing particulates and biologicals to a degree.

Their rational for reducing VOCs seems to be based on a misunderstanding of the science they quote.

It is so easy for any company to back up their claims with simple testing in real homes/offices. At best they will publish misleading data from environments that aren't relevant to the real world.

I recently posted this on another thread. I'd really be interested in GPS's response.

***************
I have doubts about GPS claims of VOC reduction.
Here's a quote from GPS's website:

"The ions breakdown harmful VOCs with an Electron Volt Potential under twelve (eV<12) into harmless compounds like O2, CO2, N2, and H2O."

Very sciency sounding but very unscientific. Electron Volt Potential does not refer to the ability to break down VOCs into harmless components but to ionize different molecules. This simply means that outer shell electrons are added or subtracted. There is no breakdown of the molecules into simpler components. Now there may be some advantages of ionization -(1) smaller stuff will stick together to make bigger stuff and fall to the ground or be captured by filters, but good HEPA filters are probably better (2) Ionizing small biologicals "might" disrupt cell membranes and kill the bugs in questions. How effectively this is done is not clear.

But Ions, by themselves, will not *breakdown* VOCs, contrary to GPS's claim. I could be wrong and am willing to test with instrumentation if I could be my hands on a unit. I approached GPS about this and they said they already know it works and don't need my input. They pointed me to some data on their web site but it was double speak nonsense.

Non Thermal Plasma generation has been shown to reduce VOCs in scientific studies but these applications differ significantly from GPS's approach. These devices use very intense electric fields in what amounts to a gigantic capacitor usually with a catalyst of some sort. In this approach Hydroxlys are generated and these can breakdown VOCs to simpler elements. Usually these approaches also generate Ozone at the same time. The fact that GPS doesn't generate ozone, which they use as a selling point, also raises doubt about their ability to produce Hydroxyls.

If all it took was a 12 EVP to destroy VOCs, UVC lights, which also have the same EV potential, could be used to breakdown VOCs.

All the above is not to say that GPS does not reduce particulates or can sometimes kill biologicals (like UVC does) but their claims for VOC reduction are unfounded.

Maybe I'm wrong but it's easy to test - why hasn't GPS shown this? They like to advertise how they can prevent mold growth in a small fish tank or reduce cigarette smoke in same said fish tank. Why haven't the showed the same about VOCs. Also demonstrating effectiveness in a fish tank makes for impressive Youtube video's but it's a far cry from a real living space.

[IndoorAirNerd]

A few various comments:
1. Yes, there can be partial breakdown products of oxidants such as aldehydes, namely formaldehyde. So you want to break down a complex VOC with 10 carbons down into smaller chemicals? Formaldehyde is the "smallest" VOC with just one carbon, two hydrogens and an oxygen (HCHO) so it is something to look out for with air cleaners that oxidize (especially because formaldehyde is a known carcinogen).
2. Ionizing by itself does not break down VOCs or kill microorganisms, according to my understanding. Ionizing leads to reactive oxygen species (ozone, hydroxyl radicals, etc.) which has the damaging effect on VOCs, microorganisms, and to some degree... humans. Of course ions can lead to particles agglomerating, which can physically remove them.
3. Indoor air quality is complex. There is no one silver bullet. Generally speaking, having thoughtful outdoor air ventilation and media filtration (and activated carbon/other sorbents for people in polluted cities) provides good air quality without the lingering questions of safety posed by oxidizing air purifiers (ionizers, PCO, ozone generators).

[Alexe]

Interesting theme. Thanks

[Frank10]

Something in our setup *might* be working, at least on mold.

I've attached three photos of samples taken using Mold Armor DIY test kit. (There are variables here that make this a weak test, like the growth medium wasn't mixed [individual bottles were used for each dish], and the HVAC vent test petri dish was exposed for 10 minutes as the air flowed over it [per instructions] while the other 2 dishes were open to the environment for 1 hour [per instructions].)

Anyway, I thought the HVAC supply vent would grow *something,* but after 100 hours, nothing is visible, only a couple of bubbles in the agar. An open air collection near a fireplace, with the HVAC running and creating a very faint draft down the chimney produced a little growth. The dish with the most growth was placed outside about three feet off the ground and about three feet from the house. This is supposed to be the control.

I though folks here might find this interesting.

Again, our setup is (air flow) > Aprilaire 213 filter > coil > FreshAire UV-C bulb (runs about 1 hour a day) > blower > Phenomenal Aire needlepoint bipolar ionizer.

Frank

[Frank10]

From top to bottom:
1) Outdoor 1 hour sample
2) Indoor, HVAC supply vent 10 minutes running max fan speed
3) Indoor, 1 hour sample, near fireplace, HVAC running max fan speed, some down draft from the chimney

[IndoorAirNerd]

2) Indoor, HVAC supply vent 10 minutes running max fan speed

That's pretty good! A common indoor concentration of culturable mold is 200 colony forming units (CFU)/m3. If you had 100 CFM coming out of the supply register, you had around 1,000 cubic feet of air pass over the dish (which is equal to 28.3 cubic meters). So unfiltered air could have resulted in over 5,000 culturable spores passing over the dish. Getting zero colonies is a real success!

It would be interesting to repeat the experiment at different stages along your HVAC system, and do it using an impactor connected to a calibrated air pump to properly measure concentrations.

[Kszabo20]

I installed one of the gps units, the iwave-r right before Christmas. I had a 8' tall Christmas tree in my living room, after installing the iwave i couldn't smell it anymore. I run my fan in the on position through the heating season, but in cooling i run it in circulate mode for humidity reasons. When it cycles off i start smelling my house again. When it cycles on i can't smell anything. I love it!

There's a video online of it dissipating a jar full of smoke in seconds, i have done it to with a demo model we have on hand. Pretty impressive...

Sent from my SM-T350 using Tapatalk

I am considering the iwave-r for my 1900sf home. about $850 installed. Are you still as impressed with your iwave-r as you were when you posted this?

[kangaroogod]

With covid, we have been dabbling in surface testing in a residential application. Using electronic testing and swabs we can see total bacterial/virus quantities. We have done this on several homes. We did this in an employees home that happens to have a remo halo and the total sample was off thr charts almost zero ad compared to many other homes without purification installed.
Coincidence? Maybe.....????

Sent from my SM-N960U using Tapatalk

[randyf]

I am considering the iwave-r for my 1900sf home. about $850 installed. Are you still as impressed with your iwave-r as you were when you posted this?

The GPS technology might be effective for:
1. particulates
2. biologicals - with restrictions

But I find their claims about VOC reduction unsubstantiated. They seem to confuse the meaning of ionization with oxidation. Ionization is a different process than oxidation and it's oxidation that has been shown to reduce VOC with varying levels of success.

As far as biologicals go the GPS tech might be helpful in the vicinity of the device. I'm not so sure how far downstream this would apply.

I mentioned this on the GPS YouTube channel and they have sense removed comments.

[Frank10]

Folks considering installing a bipolar ionization unit might be interested in this article from the journal Building and Environment.

"Evaluating a commercially available in-duct bipolar ionization device for pollutant removal and potential byproduct formation."

https://www.sciencedirect.com/scienc...6013232100158X

-Frank

[kdean1]

Here are a few articles from various sources in the industry. There are many concerns about inflated claims and failure to reveal potentially harmful side effects of IAQ gadgets from UV to ionization.

https://www.energyvanguard.com/blog/...r-air-quality/

https://www.pbs.org/newshour/health/...U04cdmuoU-zn-A

https://medium.com/open-letter-to-ad...o-bc1570b2fb9b

https://www.classaction.org/blog/fal...JQNcHPjKQ7FF6Q