Thanks for joining me on the hvac school podcast hi, thank you very much for having me yeah. So this is um a topic that i've been really excited about. I've been talking a lot about which is in general, indoor air quality, but thinking about it more broadly um but you've been thinking about this stuff a lot longer than i have. So if you wouldn't mind just introduce yourself and how you got into this whole world of air conditioning and indoor air quality and all the stuff we're going to talk about today, yeah so uh.

Well, you go back 40 to 50 years ago, as a young engineer and worked for a few years in industry, mostly doing heating cooling at a chemical processing plant but then went to grad school and became a professor in mechanical engineering at the university of illinois for 30 years and my research has always been around energy and resources and sustainable living, the basic common thread is: how do we live on our daily allowance of solar energy? But that means how do we develop more efficient devices? How do we then collect solar energy store? It and then utilize it, and so these cover from rainwater harvesting all the way through a healthy home. That's comfortable and energy efficient at the same time, and i'm talking to you from a zero plus home in the middle of illinois, which is actually one of the worst climates in the country and and we like being in a bad climate. Just because it lets us see how we can manage those arctic blasts from minnesota and those uh nice hot humid waves from new orleans in the summer yeah the illinois is illinois is tough. Now i do notice that you're wearing a detroit lions uh shirt.

If i'm not mistaken, so where did that come from? Are you are you from that area or whatever i'm a native detroiter, yeah? Okay? Nice, even though my family moved around a lot uh that i've just stayed attached to detroit teams as miserable as they may be? Now and then but uh, but yeah detroit's, my hometown and lots of relatives in the auto industry over the decades got it yeah. Well as a um as a barry sanders fan growing up. At least you have barry to always go back on, even if you've had very few other successes. Oh yeah, oh yeah and lk live nice.

All right. So tell me a little bit about um the the company that that you're now involved with and what you're, what you're building give me. The kind of 50 000 foot view. So our company, which we're an engineering based company and the parent company, what we call newell instruments, does a lot of research and development for the hvac and our companies and of various sorts from components to systems.

But then a branch that we developed over 10 years ago that we call build equinox, it's devoted to developing technologies for sustainable, healthy and comfortable living, and our primary focus right now is the development of a smart ventilation system for homes, one that senses the indoor air Quality and then basically actively manages it as uh as a home occupants desire, but in a very simple manner. So there's a lot of technology behind it, but at the same time, that makes it easy to operate and give somebody a piece of mind that their home is healthy, yeah, just to dig a little deeper into that i've dived down the rabbit hole on this over The last few years and you're exactly right in many cases to make something simple for the end consumer. You have to make it pretty complex as a technology and what i think you're pointing out here, that i've bumped into is that there are a lot of pieces of equipment, we'll use the traditional erv or maybe the ventilating dehumidifier, that are useful and good pieces of Equipment but the control strategy, especially in a home and residential environment. It's not non-existent, i shouldn't say it's non-existent, but it's certainly not easy to set up and not easy for a consumer to manage.

So is that what you've run into? Is that part of what you've kind of designed around here? For sure i mean that was a major motivation. In 2007 2005-2007 i was advisor for uh solar decathlon team from the university of illinois. As we were looking at the technologies we were going to implement into the home, we were just seeing that what was available was just so deficient. You know, as you're hearing people describe these days with covet, that walking into a building is like playing russian roulette.

You don't know the air quality, you can't smell good air quality and we saw from field studies and our research that homes are just. You know. We rely on happenstance construction flaws to hopefully allow the wind to bring in some infiltrated air, which of course, may not be that healthy, either, depending on what passageways it takes in. And so we just start with a blank sheet of paper and, with our background, looked at what technologies we could incorporate and we came up with this device.

We call a serve a c e r and started developing that in 2008, and the very first unit is in this house, i'm sitting in that we built in 2010 and it's still purring away and we built into that sensors for carbon dioxide and volatile organic compounds. Either one of those may dominate the air quality in a home, and so these sensors keep the air at that level. As it's occupied by more people or the activities of people are increased or cooking, is generating vocs that you want to remove from the air and you're not left trying to decide whether you need to turn a dial to number one or number four fan speed. It's just doing that in the background for you, yeah, which comes down to the to the simplicity side, which is so critical so before we jump into the serve or cerv.

I just want to do a quick summary for the audience of an erv and tell me if i missed something, that's pertinent to add here, because a lot of people have never worked with any rv, or maybe you never even seen one right um. When i installed an erv on my house when i built it several years ago, uh the inspector who came and looked at it had no idea what he was looking at. He had never seen one before in all the homes he inspected even today. I would do it much differently than i did then, but i knew enough to you know, think about it and what an erv does is.

It allows for your discharge, air leaving your home to pass your intake air or your fresh air, that you're intentionally bringing and hopefully it's fresh, but it's outdoor air and those two air streams are crossing through a core and there's a exchange of energy. So in the case of an erv, you have both an exchange of sensible and latent energy, so you do have a little bit of uh dehumidification and some at least in our market. That's what we see you know dehumidification, because i'm in florida i always think in terms of florida. So forgive me a little bit of dehumidification and a little bit of cooling of that incoming air as it crosses past that air that's being discharged from the space, and that is it.

It does make a difference. But what we find is when we do a lot of the calculations. Is that often it isn't making as much of a difference as it would need to in order to really serve our market, which is why we often go to ventilating dehumidification instead of erv technology. That's just a quick caveat there, because a lot of people ask why we don't install many ervs and that's the reason yeah so did i miss anything there or anything else you would add as far as the basic erv technology yeah and that uh you know it's Basically, just operating at a steady flow that somebody sets on you know simple controls, but the one of the big problems is that that doesn't mean you have good air quality.

Another is that you don't always want to exchange energy between the incoming stream and the outgoing in the evening. Maybe two in the morning to six in the morning. It might be cooler outside and you'd, be better off in in florida, you'd be better off bypassing the heat exchanger or not trying to exchange energy because you're just deconditioning it if uh, if it's nicer outside than inside in a place like like denver, seven eight months Out of the year it's pretty nice outside, and the last thing you want to do is decondition it with with your indoor ear, and so when you put some smarts into it, it knows hey, it's nice outside. Let's bring all all that outside air in and get inside very, very fresh and then, as it warms up later in the day, hey, let's uh not be bringing in so much air, but it delays or minimizes how much air you need to bring in.

During that part of the day - and that's enormous, like you said, is that when we think about any solution - and we imagine that one size fits all or that hey, we always want to bring in outside air. Well, that isn't always the case, or we always want to exchange energy from inside to outside. That's not always the case um, and so that that intelligence uh, you know using sensors in order to make decisions that we would have to. Essentially, you know stand there all day and keep making adjustments in order to adjust for another side.

To this is that ervs tend to be designed, and they don't always have to be designed this way, but they tend to be designed for balanced ventilation. Applications where you want just as much coming in as going out, and that also isn't always the case and in our market. We would actually prefer to have a little bit more coming in than going out uh, because we don't mind a little bit of positive pressurization. In our market, yeah yeah, that's uh exactly right, so it can be tuned and you know the way the wind blows will also impact that balance or imbalance.

And since we have decoupled the two air streams, they roughly run in balance, but we use a heat pump which isolates the stream that's getting cool from the stream, that's getting warmed and either one of those might be the one coming in or going out, depending on The season, but with the heat pump, then we don't have them integrally tied together. Plus we can do more than just uh try to exchange energy. We can condition the air coming in, in your case both remove moisture as well as cool it and in the winter time, heating, the air above and beyond room temperature, as it comes in all right. So there there's a there's the real magic of the of the serve or cerv versus an erv.

I mean you could just kind of slip that in there, but this is a really big distinction. Yeah, i'm actually using a heat pump here. So, for somebody who is maybe used to heat pumps but has no idea how this would work, how would you simply explain, obviously it's easier if you, you know, go to the website and pull up an image, but for people who are just listening to this? How would you explain how that how that actually works yeah so that that heat pump uh, you know any technician. Opening it up would see a compressor.

It looks just like uh what they see in room, air, conditioner or a refrigerator and then connected to an evaporator and a condenser or two heat exchangers. In our case, we use micro channels, so very advanced heat exchangers and then uh. It's an inverter drive compressor about appliance scale, it's like about a four or five hundred watt, compressor volume, bronco and then digital controls on on the compressor speed, as well as the uh expansion valve and then a reversing valve. So we can turn the evaporator into a condenser and vice versa, on the other and basically in the winter time, at least for us, where, as we're bringing in fresh air from the outside we're heating that air and the air that we're rejecting from the house, we're Pulling heat out of that, we'll cool it down below freezing when the weather's you know nice and cold and move that heat over into the fresh air.

That's coming in we're also uh pulling moisture out of the air that's getting exhausted in the winter and that latent heat gets turned into part of the sensible heat that's coming inside and that can be a fair amount of that heat addition and in the summertime. It's just the opposite: we'll take that nice, warm humid air, that you have and will pull heat out of that and condense water out as much as about 10 to 12 liters a day when it's really humid, and then that goes in the stream that we're exhausting From the house, the serve runs at about 200 cubic feet per minute, which is quite a bit higher than typical ventilation standards for for a home, and that means that when a house becomes polluted, we can flush it out fairly fast. Respond to that that uh air quality loading and then the rest of the time, we're typically in a recirculation mode, and it may either be a powered mode where we're say in in the case of summer, contributing our roughly third of a ton capacity to the cooling Load of the house and in the winter time the same thing but contributing our heating capacity to the house. And then, if the house is in its comfort range and doesn't need heating or cooling will typically be in a recirculation mode where just the indoor fan is moving air around in the house, and this is important for a couple of reasons.

It helps even out the air quality throughout the house. Good, fresh air, that's stored, say in an unused bedroom or other unoccupied space of the house. We want to make sure that gets passed by people, and then we also it's important to recirculate. In order to remove particulates, and especially these days with contagion-laden particulates, it significantly reduces the ability of a contagion.

That's in a house, some infectious person to make someone else. Sick inside the house, so there's these different things going on within the serves management of the house. Air quality got it so when you're saying recirculation mode, what you're saying is um just make sure that i'm getting this straight when you're in recirculation mode, your outdoor air is traveling through going across a condenser or evaporator, and then returning directly back outdoors and your indoor Air is doing the same, it's going in and so essentially you're creating a supplementary um air, conditioner or heater. That's working along with your system, and i would imagine that that's especially handy in very low load homes, where you're trying to design your loads really tight, and so it gives you that additional kind of reserve energy that you can use uh as needed to supplement yeah.

We're in a lot of very high performance homes, homes that uh might just need us, plus maybe a one-ton mini split, which are just you know, accelerating in popularity and now we're seeing the uh rapid growth of ducted mini splits, where the ductless were among the first Coming in the u.s, it seems like the u.s market prefers having something behind the scenes moving conditioned air in and so we're coupled in a number of our projects with uh with ducted units. But we operate with geothermal units and radiant units and and all sorts of units, whether we operate independently or we're coupled in some manner, oftentimes we're doing the controlling sense. The controls in our unit are very advanced they're all online. We have over-the-air upgrading, which we offered that when tesla was first coming out with that in tesla, where you know each night, new features and options might get downloaded and and also now you can do this or that with your system.

So it's very advanced but at the same time as we're talking about really just plugging in a 120 outlet, it draws about 700 watts at maximum flip. The switch on and it's off and running, wi-fi is built in there's local wireless. That lets you have an array of other features and options that depend on the complexity of the house that that folks select got it, and so, if i'm imagining this correctly, then the heat pump is essentially replacing the core. So what was once so? You don't have a separate core: the heat pump is the core.

That's that's where your energy transfer is occurring, yeah got it okay. Very interesting. Yeah makes a lot of sense too, because now you have these advantageous airstreams, where you're attempting to draw air or extra or sorry dr extract heat via evaporative coil from an airstream, that's already leaving the house. Therefore, it's a higher temperature and then the opposite is true.

On the condenser side, so it gives you a lot of controls and i imagine having that um is it a is it a rotary compressor is that is that what it is it's a little reset? Oh, it's a little recent okay, but having that that variable speed, uh capability gives you the the ability to really dial that, in from a compression ratio, standpoint yeah yeah, the reset we use it's out of uh in bronco, which is uh uh more on the appliance Side, rather than say the air conditioning side, and in that gray area, where the two kind of overlap, the appliance side of compressors, tend to be quieter than the air conditioning side. Is your refrigerator is made to go in a house where you know your air conditioner is outside the house yeah. I did an interview with him. Bronco uh, a couple ahrs back is a good company.

They make a lot of really nice stuff. What refrigerant does that use, so it uses 134a, which is on the appliance side as well right and uh, but we're also poised and the architecture we've designed into this thing, such that uh. As those decisions which are you know above our pay grade, are made for the next generation refrigerants the low global warming potential refrigerants we'll be able to swap those in so whether it's a synthetic like the 1234 that you may have been hearing about or say on The hydrocarbon or natural refrigerant side that that everything's made for dropping either one of those into the unit yeah i was going to say 290 seems like that would be a logical choice so long as you can get everybody to stop being so alarmist about it. But uh exactly definitely it's all throughout europe and uh south america, and it's it's a great refrigerant and uh.

You know and you can barbecue a couple steaks with it too. Hopefully not in your attic, not uh, not ideal, not ideal, um yeah. Absolutely well great! That's yeah, that's super interesting. Where have you seen it being adopted? You know what challenges have you seen? What problems have you seen it solving? I mean.

Obviously it seems like it's a great technology, but a lot of us have never heard of it or haven't seen it. Yet, where are you from the go to market strategy standpoint we're a tiny company there's about 400 of these units scattered around north america? Now, as we tell people it's the worst marketing strategy in the world to you know, spread it out in that manner, but over the past uh seven eight years has been on the market and we're now in our second generation unit. What we call the serve two that we released three years ago, but because of the online nature of it, and not everybody wants it online, it doesn't need to be, can just be fully wired and operational. More than half of them are online and what this does is.

It also gives us continuous feedback. You know we don't have the environmental, the arrays of environmental test chambers and accelerated testing that you know the big companies have, but we are running the world's largest experiment. In indoor air quality in residences that i'm aware of, and so we're learning and incorporating those into the new machines, and so this strategy has allowed us to cut our teeth in all climate zones. The first passive house in florida for certified passive housed florida in gainesville has one of our units, as well as as far north as you can go in vermont up into canada and then over in the desert southwest.

So this has really given us great insight into how people pollute their home. How much air is needed to manage that and then how to do that in an energy efficient manner? On top of that, just seeing that our heat pump is bulletproof architecture that we use, you mentioned that you work with, like grocery store refrigeration systems, which a lot of your audience already knows are some of the most sophisticated, complex systems. As far as the defrost algorithms and control algorithms - and we kind of look at our unit as our grocery store refrigeration system - part vending machine. You know this kind of bulletproof stuff that if it fails uh, you know you've got a lot of food going bad or you know that vending machine that has to sit outside a gas station in yuma, arizona or gnome alaska.

And so that's the type of uh architecture we put in so no defrost heaters no sump heaters on this unit. Those are often you know, as your audience knows, among the first things that go bad, so this thing is just inherently protected from uh. You know ultra low charge so inherently protected from slugging the compressor or diluting or foaming the oil and stuff like that. Yeah, which is probably one of the big considerations in using micro channel as well, is that you do have much lower system charges yeah, because as soon as you said that i just thought.

Oh boy, you know like half of my audience hates micro channel because they see the issues in our rooftop units where they're exposed and they are easily damaged. But in a case like this, where it's all kind of contained and well protected, microchannel really is the right choice and, like you mentioned, we've seen this on other products that people have made there's a couple production products that potentially have a long line sets, and they In the engineering didn't think about the effects of additional charge and how that can impact on simple systems that have capillary tubes and that sort of thing, but you've, basically ticked all the boxes from an engineering standpoint. Obviously, that's your background, but you've built yourself a tank by the sounds of it yeah. For sure i mean we uh my research background at the university.

We do a lot of studies on how much oil gets entrained and carried around the system and there's always a conflict between the the compressor side of us. We want as much oil in the system as possible and then the heat transfer side of us. We don't want any oil in because it's you know, uh impairing uh and reducing heat transfer and uh, and so we're very familiar with all of those issues and basically yeah. The micro channels are great technology, uh they're in front of every vehicle on the road.

Now, driving seven well florida 80 miles an hour and uh, you know getting hit with bugs and things so they are durable. But you know you get a kid with a stick around them and that's not good. You mentioned. So you opened up a pandora's box here, because it's something that i'm in the process of trying to understand better you mentioned oil.

Carry this topic comes up a lot where technicians will say or you'll hear. People say that poe oil or uh pve oil is fully miscible in the refrigerant and then they'll say that and they'll repeat it. My understanding of this term miscible is that that is a liquid and liquid mixture so that they they make a solution. Uh, liquid and liquid, but we're not carrying oil with only liquid.

We also have vapor in the suction line and past the evaporator, and so i think it's a common misconception that oil carry based on the research i've been doing, and i was one of the ones who would repeat it, because i would hear people say that it's Fully miscible, but the oil carry still matters right, i mean, and there is still this, this issue of vapor doesn't vapor refrigerant, even if, in its liquid form it's fully missible, it still isn't fully miscible with liquid oil. Am i missing something there? It's it's a question that i have had recently. The the poe uh in the liquid phase of the refrigerant is fully miscible you, you can't see it where something like an alkyl benzene with, say, 134a or 410a is as immiscible as possible. It looks like you know: uh italian salad, dressing moving through and we've done a lot of visualization studies at the university of illinois.

Looking at how immiscible oils uh move through a system relative to miscible oils, but when the refrigerant is boiled off into a vapor say in the evaporator, the oil stays liquid and the remaining liquid refrigerant fraction is still mixed in and somewhere say the say. The last third of the heat exchanger uh, where there's still a fair amount of refrigerant to boil off it's not fully vaporized, that's where the oil makes its biggest impact, and it's just like molasses or syrup moving through it's a very viscous liquid at that point, and But the vapor's flying through and dragging that liquid, along the side of the tube from the expansion valve to say where it's about 70 quality or that you know two-thirds of the way through there, the oil impact it might cause some foaming and there's arguments that foaming Can sometimes be good because this kind of wiping in the evaporator of the tubing, with a liquid, fill and keeping the whole tube wetted is important, but the oil is not so viscous with the amount of refrigerant mixed in it with something like an alkyl benzene. You have kind of the same thing, except it floats on refrigerant. Refrigerant's.

Pretty dense, like motor oil is not that dense motor oil is a little dense. Less dense than water floats on top of water refrigerant's a little denser than water in liquid phase, and so it kind of floats along, which is a good thing. But then again, once you hit that last third of the evaporator it starts being able to grab into the wall, and now you've got this very viscous patch. That's not letting liquid refrigerant get to the wall to be boiled off, but both the the peg which you see over in the automotive systems and then the poes and other pves and things that are say on more refrigeration side.

They are fully miscible in the liquid range to summarize this, and this is completely off the topic of what we're talking about. But it's it's fascinating to me and while i have a smart engineer on the line, i wanted to ask this because i've been struggling with this. It's still absolutely true to say that that miscibility is an attribute for sure, but to say that oil is miscible in vapor. Refrigerant is, is an incorrect statement, then correct, regardless of return type, there's, maybe a little bit of oil.

That's been vaporized, but by and large it's essentially non-volatile and just stays a liquid, and this is where super heat's very critical, too, and one of the advantages of like micro channels, because in our case we don't have to worry about super heat. If we have to let more refrigerant through than what can be boiled off at a certain condition or the coil freezes up uh to us big deal, liquid refrigerant is passing through getting in the compressor, but the charge is low enough. It doesn't build up in the compressor okay, but when you do control when you're doing super heat control, so you're, essentially trying to keep that last third or so of the heat exchanger dried out now, you've got a fair amount of oil stuck inside your heat exchanger. That part of the heat exchanger is not being very effective.

You know as much as maybe a third of your oil reservoir is held up there, as well as the return line getting back to the compressor. I get it so your point being that in in a case where the refrigerant charge is so small, even if that liquid refrigerant does make it into the compressor and maybe there'd be a little bit of foaming. The oil or a little bit of you know that turbulence in the oil. It's not enough that it's gon na damage uh or actually make it into uh the point where it would really slug yeah - and this is true on big units too.

We've developed uh large military 25, 30 ton, compressor systems with micro, channel condensers in that case and then fin 2, typical, copper, thin tube evaporators, but where a 30 ton unit was using about 12 13 pounds of 410a charge in it go ahead. Let all the refrigerant freeze up the coils, let all the refrigerant pass through to the compressor. It's not going to bother it yeah and that's actually an interesting um. This goes along with something that i've thought for a long time and, of course, i'm not an engineer.

So most of the things that i look at are qualitative. You know i've observed something important. I mean that's, why we've done so much visualization because nobody's smart enough to sip a pencil and paper and theoretically figure this out, especially when you're as bad at math. As i am, but what i've observed is, it seems like we actually don't give compressors enough credit for their ability to handle liquid and in fact, we often run higher superheats to the detriment of the compressor due to overheating.

So i think we're probably killing as many. If not more compressors, nowadays, with these, you know with the way that we're engineering equipment through overheating than we are through uh, you know preventing we have this strong desire to prevent uh flooded, running and flooded starts in some cases, i guess are probably still a thing And split systems where you have long long line sets and that sort of thing yeah. But what you're saying kind of reconfirms that with modern microchannel, lower refrigerant charge, technologies yeah for sure it's a benefit and then, as you think of perhaps going to hydrocarbons or things like ammonia, which is really well suited to micro channels that getting the charge minimized. Uh.

Just on the hazard side, it has a real benefit yeah. I would love us to find more ways to utilize ammonia safely, because that is a tremendous refrigerant from the latent heat content of of that particular uh, refrigerant and reduction of charge. Oh yeah yeah, it's a beautiful refrigerant, just it's the killing. You part that's kind of inconvenient yeah, yeah yeah, it uh.

You know. Uh, a friend of mine, uh at york, says that uh. You know if only uh the freons, you know smelled bad, but you know the fact that you could inhale it and blow out a candle which - and once you know in that aspect - was a wonderful advance over methylene chloride, sulfur dioxide and ammonia. You know at that time we thought you know something had to kill you right away and now we know uh different right right, exactly yeah, it's over time, it's just as bad.

So we've talked in a circle here, but it's really good stuff. This has actually been a lot more fun than i thought it would be um. Let's talk a little bit about the problem that we're solving. I actually want to start there.

Then i forgot to hit it with the serve. I think one of the big challenges and why we don't see more of this technology because undisputedly what you've built is a tremendous solution, but some people, maybe don't see the problem. Let's discuss that for a second. What is the big problem that we're solving for? In the world that we live in today, yeah so let's say uh three problems.

One is our health and in terms of our health uh, both our long-term health, that we've been immersed in indoor environments now with materials that are volatilizing uh, as well as cleansers and other chemicals around us that we haven't been used to being submerged in before, and Uh, you know developing cancers and other things like that and then say on the short term basis that uh at current standards for ventilation, fresh air ventilation. We get sick more often even pre-covet, that the standards haven't been adequate for the basic flu and colds, which is you know well over 100 billion dollar problem a year, uh sick days and and medical visits, and then on top of that, there's the cognition problem that Your brain functions better with lower levels of co2 and vocs, and at least for someone like me, i need all the help i can get to improve my thinking. So you know keeping the air fresh is uh, it impacts decision making. It impacts your quality of sleep.

It impacts your creativity, your ability to focus and organize information, and so these are uh some of the critical factors, but the problem is that our current standards, whether commercial buildings, ashrae 62.1 ventilation standards or the residential 62.2, these are odor-based standards that basically came out of The 1930s put a person in a box blow a little air through it, and the tests which were conducted at yale in the 30s, with a recently showered and clean clothed person and then have people sniff the air coming out of that box. And when only 20 of them were dissatisfied with the air quality, that's where our say rule of thumb, 20 cfm per person came from, but you cannot smell healthy air. You cannot smell air that has a virus in it or some other contagion or chemicals that are going to impact you over a significant period of time and that's really the problem we wanted to solve. On top of that, you know over the past 20 years we've seen more than doubling of asthma and allergies, and while we don't know the causation, we know that maintaining good fresh air levels in the home is going to reduce the potential for an asthma attack or An allergic outbreak, and so what we view uh in a large part of our customer base are folks with those respiratory sensitivities and we view their home as that place of refuge, that one place where they can open a door and walk in and know that they Can relax? They can de-stress where any other building they walk in.

As we mentioned, you know playing russian roulette, you don't know the air quality. So, every time someone with that sensitivity walks in they're, really wondering am i going to be able to take a breath or you know, is something going to happen in here and stress is bad. You know, stress, absolutely put you in that fight-or-flight cortisol producing mode rather than the peaceful oxytocin-producing mode that helps you heal and feel good, and that's a big part of what we do as well is try to work with people, so they regain confidence in their home. If they've had a problem with say molds or allergens or other other things in their home environment, yeah and along the way, you know this particular product is also solving for the issue that, in some markets bringing in outdoor air is expensive.

You know it's expensive to to bring it in and then to treat it, and so we haven't really had great solutions to this problem in the past, because there's so many different considerations in order to decide how much should come in and uh what are the impacts Of bringing it in it doesn't need to be treated or not, and is it helpful to exchange you know, uh thermal energy from the from the discharge to the intake air stream. There's all these questions that we haven't really had good technology to solve. I mean i've thought about these problems in a very infantile way for years, and it's finally, we've got. You know some people who are who are focusing on building something that really does this um and it sounds like that's what you've built yeah.

I mean we uh. We've been fortunate to be in a position from our research over many years of first having the contacts within industry. So it's interesting with folks. At you know all the major companies, as well as the component manufacturers, is that nobody's ever heard of a of a device like this and and we're just now, starting to recognize the need for it.

So we're not going into a piece of into a pie that already exists and trying to grab an existing piece of pie, we're not developing, say a new air conditioner or a new refrigerator. That then maybe has 10 percent. You know difference in efficiency, but this is a whole new pie, so for any of the manufacturers, whether uh, you know whether they see a potential for themselves in the future. We're really trying to develop a new market that may have new opportunities for them as they're.

Trying to explore what is a healthy home, what are people looking for? We think we have. You know a major solution, we'll find out the market will let us know that, but we're continually growing and feeling optimistic. As you know, as we move into the future and then at some point move beyond the word of mouth, which is our main marketing effort at this point yeah and i'd like to be part of that. So if there are contractors out there who are hearing this or maybe even consumers, we have a lot of consumers who listen uh to this to try to find solutions.

In fact, i had a dentist who called me from south florida and said uh. He wanted us to help with his strategy for under air quality, because he hadn't heard anybody talk so honestly about iaq and that's what we're doing here, especially on the you know. We talk about three things more than anything else: filtration ventilation, specifically fresh air, uh and then dehumidification in our market or humidity control in general um. Those are really the three pieces of the pie.

Your product helps to some degree with all three of these. So if people want to find out more about it or they, you know, maybe are interested in purchasing one. What do they do next yeah, and so you know on our website at buildequinox.com. You know, there's both.

You know the information on the serve or the serve two now our second generation unit, and then you know form and then it's very simple, direct sales. A few places we have uh reps uh around the country, but mostly as direct sales and most the folks we're dealing with our builders, architects, uh, installers and uh and homeowners, and so it's a very simple process. As far as information, though, also on our website, you'll find a lot of resources, for example, on humidity and latent loads, which, especially, this day and age as homes are getting sealed up. More and they're, getting more latent, dominated than uh, sensible, dominated for cooling for sure you're ground zero for uh latent loads in the us you'll find a four-part report series and, as i tell people, if they're suffering from insomnia, definitely one.

If not all four will knock. You out, but you know we go through, how does moisture get generated? What amounts and it's both field study real data along with modeling, and then we talk about the climatic variations throughout the u.s and then the machines that we have available for managing it. So in florida he pump water heaters, which they'll be in every home, no ifs and butts about it. They're starting to pick up.

It's been a slow growth, but that realization's getting there and in florida you get so much liter per day of latent conditioning out of a heat pump, water heater along with some cooling and then a unit like the serve, which will also contribute to the cooling and Layton and then, whatever type of whether a geothermal or a say, a mini, split or a central you'll, get it's say, bulk conditioning for comfort and then whatever it can contribute to uh layton and then, on top of that, what's typical in your environment, uh adding then Some type of de-hum unit, a ducted d-hum unit and the serve we look at is the brains of all of that. So in florida, it's common for us to be managing the say, multiple mini splits, as well as a d-hum unit, that's directly coupled to our system. Since we have the humidity sensors built in as well as the air quality, we can manage when the d-hum unit's needed and when it's not and then uh. We have reports on smart ventilation which show you why smart ventilation is much more energy efficient.

Even though our prime mission is air quality, when you smartly ventilate, you gain a lot in energy efficiency and in florida, that means not unnecessarily bringing in moisture and - and the reason you don't see. Ervs in florida is that people are getting smart about it and understanding that well, usually where i'm exhausting from my bathroom or my kitchen and those are pretty humid areas. So even as humid as florida is, somebody takes a shower in the bathroom. That stream is actually more humid than the outside and with an erv you're, actually transferring more moisture into that already humid outside moisture and creating more problems.

We're always benefiting the moisture balance as we operate yeah because you're using sensors versus just guessing. Yes, exactly yeah and i imagine another thing that a lot of people think when they hear about sensors, including me, is that you know well. Sensors have problems but um. I imagine you've taken a lot of uh care in choosing your sensor technologies.

You bet, but i mean you still just never know you know that accelerated testing. You know, as we have a five year warranty, you know you're just waiting for that. First unit, you sold, you know back in our case 2013 to hit five years, and then you have a celebration. As you know, you know more units make it through that and sensors are a big part of that.

You know you know five. Ten cent part with a unit - that's in northern vermont or you know, uh southern florida that gets expensive to repair, and so we've been very careful on that. But we use all the best and, as i mentioned, you know our background. We've designed a lot of conditioning units for like military applications, so we're used to mil-spec - and you know everything is top quality industry.

Uh, leading compressor and components are all built into this, absolutely great um. So one more time, what's the what's the best website uh, where do people go to find out more build equinox.com and check out the multimedia section to see our newsletter and a bunch of reports and webinars that that take you through the serve? But then there's a lot of documentation on that as well and and a lot of features beyond just the basic unit that folks may uh may enjoy seeing ultraviolet air purification. We just came out with that feature zone dampering as you get into larger, more complex homes, as well as a array of battery-free wireless switches and other devices that communicate with the serve to tell it the bathroom needs to have ventilation or somebody's occupying this space or Air quality in this space is out of range excellent. Well, whether you like it or not, um based on this, you have now become my ventilation expert, so i'm going to be irritating you a lot moving forward so well, i i'm more than happy to do that.

As well as uh, you know i been fortunate and as well as being old and decrepit, you know having a lot of contacts in the industry. So, like you know, if i can't answer it often i can find someone who can absolutely well. Thank you. So much ty, it's been a real pleasure yeah.

Thank you very much, brian we'll we'll be in touch. You.