This episode of the HVAC school podcast is made possible by our excellent partners, carrier Mitsubishi, Electric cooling and heating. You can find out more by going to Mitsubishi comfort, comm the UE iHub smart kits with their thermo hygrometers, induct temperature and humidity probes and their pressure probes. As well as the UE iwrs Wireless scales, great-great kit, and find out more by going to UE, I test comm, also refrigeration technologies, makers of the wet rag product, Viper cleaners, nylon. That has become so ubiquitous.

In all of my conversations, including my recent article, on making a proper Flair, you can find out more by going to refridge tech, dot-com, refr, IG tech, comm, and you can get refrigeration technologies items products from true tech tools. Comm TR you tech tools, comm offer code, get schooled for a great discount, also want to thank arrow, Asus makers of the bipolar and Nano whole home air purification products. Quick mention to a couple other people who are not technically sponsors, but who are definitely products that I use I'm very thankful to retro tech, who makes great blower doors and duct leakage. Testers right.

Soft you can find out more about, writes off we're going to write soft calm, write soft makes excellent software for doing manual, J and manual, d-duck design and load calculations, and then also tube is pal org and Patrick long for helping me do some recruiting lately. Biz Bell org has an excellent system for finding new employees, so if you're in a business that is in need of some help, take a look at biz. Pal org beat zoom lock the 10 second flame free refrigerant, fitting from Parker reduced labor costs by sixty percent. With no brazing no flame had no fire spotter discover how Siouxland can help you be more efficient and productive visit.

Zoom lot comm for more information, he's creepy in a good way, Brian or here d, hidey-ho d, thanks for listening to the hvac school podcast, the podcast that helps you remember some things that you might have forgotten along the way and also helps you remember some things That you forgot to know in the first place I am Brian and I went down to Austin Texas, never been Austin before flew down Austin Texas and got to hang out with a bunch of really great people at the humid climate conference. This episode, as well as the next one, which is with Corbett Lunsford, were both done, live at the humid climate conference and so they're a little different than our usual episodes, but because they were done, live you're gon na hear some background noise because we were doing Them right there, the humid climate conference is an absolutely great conference, big thanks to positive energy and the building science podcast for helping put that on Christoph over there I met Miguel and then I also met John Harris, who is who we are interviewing for this podcast Sean is the proprietor of Aeroseal Austin and he's also a tester for positive energy. Positive energy is an independent HVAC design firm that helps design some really high performance systems in Austin, Texas and sean is a practitioner he's a guy who actually does it and it's nice to talk to people who are trainers and educators. But it's also nice to talk to people who actually do this work before we get into it, though, because we are gon na talk a little Aeroseal we're talking about sealing ducts from the inside out, I want to say I was skeptical about this product when I First heard about it, but I have since changed my mind.

We don't do it at kalos, so I can't speak personally from the experience that we have, but the question of why you would want to do it. I think it's important for us to answer that. Real quick and the reason why you want to seal ductwork, so it's really tight so that you can control what's coming in and out of the house. Obviously so you don't want to be sucking in attic air and then dumping it into the house, but you also want to control the pressures in the home.

So if you have supply duct leakage, which is common, if you have supply duct leakage, then what occurs is. Is that the house tends to go under negative pressure because you're losing some of that air to the Attic and when the attic or crawl space or wherever the ducts happen to go? I'm used to Florida and in Florida everything's in the Attic. But if you're blowing air out of your supply duct into the conditioned space, then that air has to come from somewhere, which means that the house then goes under negative pressure, which just isn't good, especially not good, for controlling relative humidity. We would much rather that you bring in outside air through something like a dehumidifier or an ERV rather than bringing in outside air, because you have imbalanced pressures and you're, sucking it into the wall cavities, and all that, because I can be some pretty nasty nasty air, Especially when you're in a humid climate, like I am here in Orlando or like we were at when we were there in Austin or Houston, a lot of other places pretty much any time you're on the Gulf Coast, all the way up through sort of the eastern Seaboard, there's a lot of moisture issues even in a place like Ohio, there's, a lot of moisture issues so anyway, this whole duct sealing thing becomes even more important when you're really trying to keep your pressures balanced or even positively, pressurized inside the home.

In fact, in humid climates, it's better to even possibly pressurize so obviously leaking supplier in the Attic is a bad thing, because you're losing energy just because you're leaking that air out. But it's even worse, we start to talk about what happens when you put the house under negative pressure. So that's why we're talking about it? And so here we go Sean Harris with positive energy and Aeroseal of Austin. Talking about sealing your ducts from the inside out with Aero seal all right, so we are here at the human climate conference in Austin Texas, I'm sitting here with an austenite Sean Harris with Aeroseal of Austin and positive energy.

So thanks for sitting down with me for a second Sean thanks for having me Brian yeah, having you you're having me, because I'm here in Austin, oh yeah, thanks for having me okay, so I wanted to just go over real, quick we're gon na talk more about Aerosol and some podcast coming up soon, but I wanted to just get your kind, a quick overview of what Aeroseal is and how you use it, because you're actually a practitioner, that's what I like people who actually do this stuff every day cool. I started out in the building science industry testing homes and looking at duct leakage and how it impacts both new construction and pre-existing homes. And I realized that there was a major problem out there that HVAC companies were struggling to steal their ducts even in brand-new homes. But if you go into older homes, it was also just as bad.

Even worse. You go back to metal ductwork that had no fluid applied. Sealants whatsoever now is inaccessible due to a low pitch roof for she rock in the way, or things like that, and I saw this product aerosol and I was very skeptical. I didn't think that it was going to work, didn't think that it was gon na last and so it took, I don't know a year and a half or so before I really looked at the product closer.

I went and watched an air seal being performed and I felt the product and felt how it maintains his elasticity and how it can stick to two different services and really sort of maintain that hold for years and years anyway. So that's what sort of got me into doing it aerosol, if you guys don't know, is a product that can seal up air-conditioning duct work similar to fix-a-flat for a car tire, so it automatically just goes and finds the leaks and seals them. Basically, we do that by isolating the duct system, so we put some closed cell foam plugs in at the unit, as well as at the supply and return registers. So we've isolated just the duct system.

We then pressurize it introduce an aerosol into the pressurized system right and then the air flow goes around, circulates it and then, wherever there's a leak, the aerosol is drawn towards that spot and it just starts building on itself and sealing the leak and it concealed leaks Up to five eighths of an inch well a couple things to address right away because the cartoon in our head. I think we imagined this stuff like going into a duct and like covering all of the surfaces inside the duct. When I first heard about Aeroseal, that's how I imagined it, but that's not actually how it works correct, so it doesn't coat the duct work, I'm lucky for me, the sealant is very expensive, and so I'm actually happy that it doesn't cut the duct work but yeah. If there is a crazy amount of leakage in the system, sometimes the bottom of the duct work gets a little tacky, but there is no coating of it.

It just goes to wherever the leaks are and seals them up got it. So I'm kind of imagining, because it's a pressurized duct system, it can't go out of the duct system. The air is only escaping through the leaks and so it kind of bonds as it hits that low-pressure area and kind of bonds right there. At those points exactly yeah, so we already mentioned fix-a-flat and I think a lot of technicians are rolling their eyes.

I got jeez fix-a-flat and then we also talked about internal leak sealants for refrigerant systems. I think also works. Similarly, where you have that attraction to the edge surfaces and attraction to each other is what bonds, but it's only at that leak point it's not like it's gumming, the ductwork somewhere. So, just to kind of give your credentials, though, because you it's not like you decided one day hey, I just want to start doing era, so you had done a lot of testing on systems prior to that and see you actually saw the demand.

So what type of testing had you done prior to getting into Aeroseal? Yes, so I first started working with a company called positive energy and it's a building science company. That's now predominately does integrated mechanical design, and so they do manual Jay Manuel de Manuel s and things like that, but they also start out as testing houses. That's how we got our start. Looking at building envelope assemblies looking at duct systems.

Looking at how the house functions as a system of systems from there, we realized that testing houses testing. The duct leakage in particular was a major issue that sort of affects all the other systems in the house right and so then, in the process. You were telling me this earlier, like in the process of doing this duct leakage testing. You end up bumping into a lot of circumstances where it's like.

What do I do right? In some cases you can seal it manually, but in a lot of cases you don't have that option. I mean there's just not a good way to get to the ductwork correct, oftentimes, it's especially back in the 70s and things with low pitch roofs and fir downs that have the ductwork in them. There's no way to access the ducts other than to take down sheetrock. So when I'd be going in doing these sort of energy audits on older homes, I'd measure the duct leakage and it was excessive and I would say yeah, your only option here is to take down sheetrock and that's really invasive into.

What's going on inside the house and also expensive and aerosol just seemed to be the solution, it's not by any means to fix all this is not to put a bandaid on things: the gray mylar flecks from the 80s. We turned down a lot of work where people are like. Oh yeah, coming in seal my ducts. This is not the answer for every single problem.

Duct replacement is important. Good quality work is important era seal the duct system - I don't think - is going to last another six months or something that's not what I do. I'm about doing. Good quality work you're in the business of doing Aero seal, which are also in the business of designing, really good duct systems as well.

So it's not like you're interested in just aero sealing everything when it's not the right solution for a particular problem. Correct and oftentimes ducts are undersized, both supply and return. Ductwork is undersized and sealing. It just makes those problems worse.

So, looking at the whole system, not looking at selling a job and doing something for somebody, but actually improving their circumstances is what I'm. After one thing you had mentioned is that you will, in some cases, manually seal a system and if it's accessible often, I think you do that anyway and then you'll retest and find that it's still significantly leaky right, correct. Yes, so there are times where I'll go in and we'll do a duct blaster on system and they'll, be, let's just say, 250 CFM of leakage, and I'm like oh yeah, I'm gon na get all that and there's probably a good 60 CFM at the unit that I can tape up, and so we can really knock out this leakage without needing to do much air seal and I'm surprised at how much leakage is left. I know where the leaks are.

I get to see aerosol leaking out of a lot of different places, and it's given me a lot of experiences on where the leaks are, and I just can't access everything all the time and that's what I really like about aerosol is in conjunction with hand, sealing You can really just get all the leak and get it all yeah, so one thing that they talked about a lot at the conference. The humid climate conference is indoor air quality. Obviously, but one thing that came up quite a bit, and especially in one talk, was how you really don't want hose on inside unless there's a reason for it and a lot of indoor air quality products do put off of ozone. In fact, air Oasis even will tell you that they're nano product does put off a little ozone most, if not all, PCOS put off a certain amount of ozone.

Pc o stands for photocatalytic oxidation, but airways's makes a product called a bipolar ionizer. That does not create ozone. The bipolar ionizer, splits, moisture in the air into positive and negative ions and those positive and negative ions go out and they bond to particles in the air, and it really helps reduce particles. It does help with odors and it does not create ozone.

So we really like the bipolar ionization product. It's easy to install you just install it on the side of the blower. It's very well built. It has no moving parts lasts a really long time.

There's no bulbs to change or anything like that, and so it's a nice product. If you have a customer who's interested in getting started with some advanced indoor, air quality, air purification types products, so remember, air, oasis and their bipolar, ionization air purifier. You can find out more by going to air oasis calm. One more company I want to mention to you is refrigeration technologies.

You can find out more about them by going to refridge, techcom and a product that i want you to be aware of. Is their wet rag product and how wet rag works? Is it's essentially just a little canister? It has a screw on top a real nice kind of compact little canister and inside there it's hard to explain. But if you remember the old putties that we used to use in order to help protect items when we're brazing, it's kind of like that, but it's almost like moon sand. I don't know if you've ever played with moon sand with your kids, but it clings together and it has some moisture content to it and it really helps protect like line dryers or accumulators.

Compressors service valves expansion valves things that you really need to make sure that you're not going to damage the internal parts, and you also want to make sure you're not going to burn the paint. Wet rag is a really nice product and when you're done with it, you just take it off, put it back in the canister, and you can rehydrate it with just a few drops of water, even if it starts to dry out really nice product made by a Very good company, I'm a big fan of refrigeration technologies. You may notice that I'm really going for US companies where the founders are still involved in the business's refrigeration technologies. Is that way, Eero asus? Is that way companies that invest in the trade and who are making really good products and I'm very happy to be working with refrigeration technologies? I see them as sort of the pinnacle of chemical manufacturers in the HVAC our space.

They were started by a technician. Many years ago, because he saw a need to make some great products and I'm very thankful to them for the investment that they make in the trade so again find out more by going to refrig techcom alright. So you just said something that i want to hear. More about you see a lot of leaks.

You know where a lot of the leaks are give me like, maybe the top two or three places that you see air leakage regularly yeah. So it depends on the duct design, but it always leaks at the connections right. So, on flex, duct, for example, people think that not using fluid applied sealants, where the flex duct connects to a starting collar is acceptable, and I see a lot of leakage at those points. It doesn't look like it because there's a Panduit strap on there.

That's pretty tight, typically there's a circular starting collar that sometimes oval eise's and you don't know it what's cool about air seal. Is that it's like a fog that goes in, and so when we have really leaky systems. This fog comes out into the attic and we get to see where the fog generates from and that often times it's those connections. We see it, we talk about the fog.

Are there ever issues with that? Getting on furniture or anything inside the house? Do you have to protect for that? Sometimes we do what I mean by that is air seal stay suspended for about 20 minutes or so in the air, and in that time we have air scrubbers. We have fans that we can put in windows and things like that. Every still has to come out to the leak in order for us to actually seal the hole, and so sometimes we do end up falling out a room or something like that. But we've got plenty of ways to get the fog out of there before it settles.

We do often put down sheets of things over furniture couches, expensive, artwork, things like that get protected just in case. Ok. So if you're doing this like, if the Louvre in France, you would cover the Mona Lisa that sort of thing - okay, I wan na mention positive energy. It's been great meeting you.

It's been great meeting Christophe, really a great company. I think there's probably going to be some of you out there who are in the kind of the high-end air conditioning side of things where you need to have things designed really well designed, and maybe that's not your forte. I would strongly recommend that you look them up and find out what they do: they're just great people. They have an excellent podcast, the building science podcast.

So take a listen to that. It's really good quality podcast a lot of great content. I would suggest listening back a couple: episodes too there's one: that's titled architectural yogurt. That was a very interesting episode.

I enjoyed that quite a bit. I may actually have that guy on HVAC school here soon, but yeah. Thank you so much for taking the time to do this and yeah Aeroseal sounds like a pretty interesting thing. One other thing that I will add in closing here when I first heard about Aeroseal, because the aerosol used to have a relationship with carrier.

I don't know exactly how that worked, but I heard about it years ago and it sounded like bogus to me like when I first heard about like ah whatever this doesn't work, but since that time Bill spawn is a big fan of it. I don't know that he's done it in his current house, but I know his partner. Eric has done it on his house and then Jim Bergman had it done in his house as well. And you know those guys aren't gon na back something unless it actually works and they speak very highly of hero seals.

So I really, I believe in it. I think it's something to consider for your business if you're, in a position where you run into these type of circumstances where you need to solve these problems. So thanks for having me Brian yeah, it was great. Thank you, alright, big, thank you to Sean Harris.

Thank you once again to positive energy for putting on the show. I know I keep mentioning this, but I was just really impressed by the human climate conference. They did a really nice job with it. It's great to meet people who are doing good work, who are excited about the work that they're doing.

If you ever need some really advanced HVAC designs done, so you work on a really big custom home or something, and you need some consulting or some designs. I would definitely suggest that you look up positive energy and you see the work that they're doing and maybe hire them. If you have a job that requires it. If you haven't already check out the building science podcast that's put on by them, they do a nice job with it.

Also, if you haven't heard our other podcast, you can find our other excellent podcast in the blue-collar roots Network by going to blue-collar roots, comm and another similar show a show that kind of covers some of the same sorts of topics and a little bit different style Is Bill Spohn and the building HVAC science podcast? So take a look at that. I don't know if you're aware of this, but when the Sun yeah the actual Sun in the sky, when he was in his 20s, the son's parents came up to him and said son. You need to go to college and the son said why I have like 27 million degrees already all right, thanks for listening, we'll talk to you next time on the HVAC school podcast, thanks for listening to the HVAC school podcast, you can find more great HVAC. Our education material and subscribe to our short daily tech tips by going to HVAC our school comm.

If you enjoy the podcast, would you mind hopping on iTunes or the podcast app and leave us a review? We would really appreciate it. See you next week on the HVAC school podcast.