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Is 400 CFM per Ton Always Right? w/ Ty · HVAC School - For Techs, By Techs

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He's got more airflow opinions than most people have tools.
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It's your host, Bryan Orr.
2:18
Yo yo, yo yo yo, what's up?
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My brothers and sisters in the HVAC trade.
2:24
Thanks for listening. This is the HVAC School Podcast.
2:27
I'm Bryan. Bryan Orr, if you must know,
2:29
and my name is spelled with a Y and my Orr is spelled with two R's.
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And, you know, if you hang out with me,
2:35
you'll never be up a creek without an Orr.
2:39
Wow, that's rough. And it's always rough when Ty and I talk.
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There's lots of dad jokes, although not too many in this episode,
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frankly. But Ty Branaman of Love2HVAC, great guy,
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one of my very good friends in the trade and somebody who helps us at The Grit
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Foundation. Find out more at TheGritFoundation.com.
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When I say he helps us, honestly, he does all the work.
3:00
Ruchir Shah and I came up with the idea and put together the structures,
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but Ty is the one who goes to the camps and makes them real and helps lead education
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for what we do at The GRIT Foundation.
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So check that out.
3:10
See if you want to be part of it or if you want to support.
3:12
We would always appreciate that.
3:13
We have a lot of really great people like Eric Kaiser.
3:16
It's always helping out at Grit camps.
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Danny Mulzitt is another one who comes to mind,
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who's helped out a lot.
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Lots of really great guys who make it possible.
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Guys and ladies. I don't know why I'm just saying guys.
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So many people. Sue with TruTech Tools has put on a couple camps.
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She does a great job with it.
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So many great people who have helped out with that.
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But that's not what we're talking about today.
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Today, we're talking about 400 CFM per ton.
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That rule of thumb, where it works, where it doesn't,
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where it came from, and then how to think about times that you need to adjust
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it. We're not going to talk through any boring math here.
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We're just going to kind of riff on it a little bit.
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Ty and I talking about 400 CFM per ton.
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Ty, how the heck are you?
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Doing great. Life is a breeze.
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Life is like a box of disgusting dark chocolate.
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You do know what you're going to get and it's going to be disappointing everything.
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Just kidding. It's like a breeze in a 130 degree attic at 90 % humidity.
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It's like a breeze coming off of an exhaust fan from the bathroom of a w***.
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We're talking about the whole CFM per ton rule of thumb,
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the good old rule of thumb.
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So what is that rule of thumb that oft gets repeated,
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Ty? Oh, man, 400 CFM per ton.
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The rules and oh, it pains me so much.
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Of the rules of thumb, at least it has some valid cores to it.
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I like how Alex Meaney explains it.
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He's like, look, we're going to put this brick here.
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It's not a brick, but we're going to put this to hold a shape and we're going
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to come back later and replace it.
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And so many people have used a 400 CFM per ton.
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We've put that in there and we just thought that that was like an actual brick.
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And it's like, no, no, we need to replace that with some more details.
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That's what we're going to talk about today.
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We're going to use Alex Meaney's beautiful example there.
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We're going to take that holder out and put an actual brick in there that you
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can leverage on. Yeah, the term that Dick Wirz uses in his book is rot,
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or I think he calls them trots, but I always do rot.
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Rot is a rule of thumb.
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The problem with a rule of thumb is it's like wood.
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It's good, but then eventually it's going to rot on you.
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It's not always going to apply.
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And that's the case here, too.
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400 CFM per ton is just a rule of thumb.
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It's a starting place.
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It's something that helps you build that.
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It's a scaffolding that you build around, but eventually it doesn't stand up.
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So let's start with the basics here.
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We're going to talk about where it actually can be pretty accurate and then where
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it gets increasingly inaccurate.
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So let's talk about first, why do we say it in the first place and why is it
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sometimes does apply actually?
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Well, you're talking about standards.
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You have to test of a piece of equipment and you have to test it under a set
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of standards. So you have to come up with some hard rules like,
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hey, we're going to test this under these basic rules.
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And in those rules, what are we going to have for airflow?
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Let's set 400 as our CFM.
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So now we know the outdoor temperature, the indoor temperature,
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and the humidity, and how much air we're moving across the coil.
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So that gives us a good test point.
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And under those test points is also where you get the magic 40 degree evaporator,
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because under those test conditions, that's what your evaporator will be.
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Not that that's what it's going to be all the time,
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but that's where that comes from, basically from the initial testing.
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And it also just makes sense.
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There are limitations that we have in compression refrigeration in the types
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of equipment where we're air to air types of equipment,
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because we don't want our evaporator coil to drop below 32 degrees.
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Correct. So we can't have airflow so low that it drops below 32.
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And we still want our coil to be below dew point in most cases,
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in most green grass markets.
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So that way we can drain some moisture out of the building.
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And so somewhere in there is a level of airflow.
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And 400 happens to be right in the middle of that,
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where you're condensing moisture on the evaporator coil,
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and you're not freezing it up.
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We can't run our evaporator coils with too low of airflow for lots of reasons,
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even if we wanted to from a de -emitification because of freezing.
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And if we run too high of air flows,
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you will hit a point where that evaporator coil is no longer making water.
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Making water. But again, that's under normal green grass conditions,
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what we typically see, typical sea level situation.
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That 32, once we get our saturated temperature below 32,
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that's what I call the Hans effect.
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We want to keep away from that, because that's Hans so low that it's going to
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freeze up. Did you just think of that just now?
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You said so low earlier.
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And I was like, I couldn't hear anything you said.
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I was like. Right.
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You're just looking for a way to shoehorn that in there.
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That's all it was.
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100%. Yeah. So talk about cases where you're running into really dry conditions
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and cases where you have higher altitude and how that can affect what your targets
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would be as far as airflow.
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Two huge things. One thing that's really benefited me is how many different places
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I've lived. So I've lived in Miami.
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I've lived in Texas.
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I've lived in Phoenix and Nevada.
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So I've lived in Australia.
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So I got to see a lot of different climates.
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And so it's been huge and changing my thought process of this is the number that
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you need. So in Las Vegas, it's dry.
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You don't need dehumidification at all.
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Like it's that one day that it rains.
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So most of them, you don't need dehumidification.
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Your air is already too dry as it is.
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A lot of the singers there have humidifiers in the middle of summer.
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They're humidifying to keep their voice good so that they can continue to sing.
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So how do you prevent dehumidification?
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More airflow. And more airflow makes the system efficient if you're considering
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sensible heat only, sensible capacity.
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So having more airflow is good.
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So yeah, we can get the cold temperature up moving more air.
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Take exchanging heat at a much faster rate.
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It makes everything more efficient.
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The air is moving through the duct in the attic so fast you're not losing as
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much heat. So it's just all around a great win for that.
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So we're looking at much higher.
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450, even 500 CFM per ton.
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That's a great thing.
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The duct work has to be able to handle that too though.
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But there's no reason to have your coil at 33 degrees in Las Vegas and trying
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to pull a little bit of water out of the air as you can.
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Now you've got this low-temperature air traveling slowly through this duct work.
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You're having a lot of heat gain in it.
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It's just all around loss.
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So in that condition, then yeah, hey, let's speed the air up.
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Make sure the ducts don't handle it.
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Speed the air up and just everybody wins on it.
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But like you said, also we have the altitude.
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And what's cool about Las Vegas is you have Death Valley right around the corner
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of that sea level.
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Las Vegas is 2000 feet.
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And you got Mount Charleston, which is a 45 minute drive.
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That's 8 ,000 something feet elevation there.
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So you have like all of this going on at the same time.
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And a friend of mine, Mike Lindsay in Las Vegas,
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he does, he's a lab technician his whole life.
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HVAC specialist, complete nerd, love him.
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And he does this testing with airflow and he goes out into the desert in his
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spare time and he sets up all this gadgets at sea level,
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finds the exact sea level and does all the testing with different weather conditions.
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And then he goes up to like Mount Charleston and he does all the testings at
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altitude to see for himself, like how weather changes and how different temperature
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and humidity changes all of his numbers.
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And he tests different ways of measuring air.
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And that's where I really learned about the difference between SCFM and other
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CFMs. Actual, yeah, actual CFMs.
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And I still get them mixed up because I don't do it daily enough to keep it lined
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up. But when he starts talking about capacity of a system and how,
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hey, we're moving so many CFM of air,
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but because the air is a lot thinner,
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even though you're moving so many cubic feats of air,
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you're not moving as much volume of the actual molecules.
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So you're not changing as much heat.
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So it changes the entire capacity of the system.
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And it just blew my mind that he had to change the ratings of the system to account
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for the airflow. And I just never done it.
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We just, hey, it's a four ton, we install it.
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And so he changed my entire thinking about CFM capacity,
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all these other numbers.
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So being in Vegas was huge for me because I got to see a bigger side of it.
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Yeah, because it isn't a directly linear calculation.
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It gets actually pretty complicated.
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So let's see if I can basically explain this without boring everyone with numbers.
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When we say SCFM, it's essentially locked in at the density of air at sea level.
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So you're pretending as though, if I'm moving 400 CFM at Death Valley and I'm
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moving 400 CFM at the top of a mountain,
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that it's moving the same density, the same pounds of air,
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but it's not. And so that's the thing.
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We could be moving, and I like how Jim talks about it as boxes of air.
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I've always used that.
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And so if you're moving 400 CFM at altitude,
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you're moving the same number of boxes.
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The boxes just don't weigh as much.
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And what does the coil care about?
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The coil cares about the weight of the air much more than it does the boxes of
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air. But the thing is, is that you,
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then you also have the speed of the air.
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So if you just try to move more air to do the same,
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so all we got to do is just move more air over the coil.
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The face velocity across the coil is still proportional to the actual volume
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of the air. So now you have more molecules,
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technically, because you're rushing more paths, but they're going faster.
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And so now you're dealing with face velocity across that coil.
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And if you're thinking about that boundary layer of these little air molecules
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touching the metal in the coil, just moving more faster doesn't necessarily get
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the same proportional result.
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It's not like you can just graph that with a basic linear chart.
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And so the point is, is that it's harder to move heat into air or move it out
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of air into a coil in altitude makes perfect sense.
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We also have density adjustments that happen at different humidities.
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It's not as nearly as significant as altitude,
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but it does. Air that is more moist is actually a little bit less dense.
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And so it's the same thing to a much lesser degree.
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A lot of people think that's wrong because they think of air as being heavy.
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And every time I have to do that in my head,
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it's like, I don't know, but actually water vapor is less dense than air.
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And I know some people are going to say,
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he's wrong, you made a mistake.
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I'm not talking about liquid water.
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Liquid water is obviously more dense than air,
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but I'm talking about water vapor.
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That's why water vapor rises.
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That's why we have clouds.
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So there's all these little controlling factors.
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And so when we say SCFM, we're just locking it in at sea level and pretending
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it's the same everywhere.
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And the result is, is that when you have some of these various conditions,
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a lot of times you do need more airflow to do the same work and sometimes significantly
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more airflow to do the same work to get the same pounds of air over that coil.
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That's the beautiful thing about what we do.
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Like Willis Carrier, when you look at the psychrometric chart,
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he was able to map the air.
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And because he can see what the air is doing,
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then he can see what happens when he modifies it.
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And so all of these engineers and scientists have done so much this work before
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us. And they've given us these parameters to work with.
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And it's cool, funny equipment.
13:22
Most people never looked at what the actual rated capacity is and then how that
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capacity rating changes under these different conditions, under different humidity,
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under different indoor and outdoor temperatures, different humidity,
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all of that. But they've charted us all out for us.
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Now, when you have that chart, it's all digital now because we used to put the
13:38
chart we had to put it in a pocket and that was bad because you would have a
13:41
chart in your pants, you never wanted that.
13:43
But now you can have your chart on your phone and you can look up this data and
13:45
you can see what it's going to do under the conditions.
13:48
So if I'm installing one at altitude in a dry climate,
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in a humid climate, what is that equipment going to produce under these conditions?
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And then we can compare and know, hey,
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what are we trying to solve?
13:59
Which equipment is going to do that?
14:00
Because a four tons is not a four ton system.
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And that's actually a really good point.
14:04
There's a couple of different ways in which when we say 400 CFM per ton,
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we're making a simplification on several different sides.
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And that's where it's not bad.
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It's just very inaccurate.
14:17
It's using a very dull knife to cut with.
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And so we've talked a little bit about how air isn't always SCFM.
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And so if the altitude changes, humidity changes,
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temperature changes, those are all factors.
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We also talked quickly about how in some markets you actually want higher air
14:32
flows because you don't want to be wringing moisture out of the air.
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That's the high end of that.
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We started by saying you want to be in the middle somewhere between freezing
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but also below dew point, unless you're in an arid climate where you actually
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don't want any moisture taken out of the air.
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So we mentioned that and that's all on the air side.
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But then on the equipment side, it's also a moving target.
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And that's what you just said.
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If you have a four ton system and we're assuming that it's 48 ,000 BTUs per ton
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and it's a certain number of CFM per ton,
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what's actually more accurate is the number of CFM per BTU.
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That's actually a more accurate way of doing it.
15:01
And it's even more accurate if it's actually a pounds per air per BTU.
15:05
That's actually when you're now we're starting to dial it in.
15:07
And again, you could have a 48 ,000 BTU piece of equipment and based on the exact
15:11
match of air handler and condenser, it could be 46 ,000 BTUs.
15:16
Then you have the actual conditions that it's operating under.
15:19
Maybe it's higher temperature or whatever humidity is different.
15:21
Now that can de -rate.
15:23
And then you could have all we actually went down to a three quarter instruction
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line, which is actually allowed, but it actually de -rates the capacity a little
15:29
bit. Okay, now that de -rates and oh,
15:30
actually it's in a commercial space.
15:32
So it's on 208 volts instead of 240 volts.
15:35
And now that de -rates a little bit.
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And so you could have a four ton system that ends up being 38 ,000 BTUs by the
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time you have all of these de -rating factors.
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And so what's more important is not that it's four tons,
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it's that it's 38 ,000 BTUs.
15:48
And it's not 400 CFM per ton.
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It's a particular number of pounds for that climate of air per,
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what did I say, per BTU of system operation actual.
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So actual BTUs operation.
15:59
And that's where it gets really, really useful because you're going to hear this
16:02
and like, well, how the heck can we do that?
16:03
That's where tools like measureQuick or great because it can help correct for
16:07
all of this. It can correct for both sides of that equation and tell you whether
16:10
you're in an acceptable operational range or not based on the real rated capacity
16:15
of that equipment under these conditions, not just the nominal capacity that
16:19
you read off of a model number.
16:23
All right, going to take a second to talk to you about Refrigeration Technologies'
16:26
WETRAG. It's a product that our techs have used for a long time.
16:30
Works great. It's a heat blocking putty that works just like a wet rag.
16:33
You put it around valves while brazing, put it in a valve inlet,
16:37
your service valves, your evaporator, your service valves,
16:40
your reversing valves. If you're replacing a reversing valve,
16:42
heaven help you, but this really works great for that.
16:45
TXVs, electronic expansion valves, reusable up to 40 times with dye that lets
16:50
you know when it's nearing the end of its life.
16:54
Easily withstands our torch temperatures and protects things like we talked about
16:58
compressor, paint, reversing valves, line driers, suction driers,
17:04
liquid line driers, bi-flow driers, basically all the dryers.
17:07
It's great for dryers, especially the ones with the really short stubs.
17:09
Pain in the butt.
17:10
You don't want to burn that paint.
17:11
You don't want to create rust on those new dryers that you put in.
17:15
All you have to do is take it out,
17:17
put it around anything you want to protect,
17:18
then put it back in the container to reuse it.
17:21
For larger areas, we've talked about this a lot,
17:23
Refrigeration Technologies also has introduced the HeatShield which you can
17:27
use wet or dry and cover a larger area like the front of an air handler or a
17:33
case evaporator coil, for example.
17:35
Also great for air-acetylene or swirl tip torches or they tend to blow out a
17:39
lot more heat on the convective side.
17:41
Works great for that.
17:42
Find out more about the original WETRAG as well as heat shield by going to refrigtech.com
17:47
Now, I just want to make a little pause here because if
17:53
I'm talking to me many years ago, I'm like,
17:56
you're going way too deep.
17:57
You don't need - This is way too much,
17:58
right? Exactly. So as an example, it is relevant.
18:02
Let me put some relevance to you.
18:03
There's these things called these Chinese diesel heaters.
18:05
So people that do off -grid living, they put the Chinese diesel heater in because
18:09
you get the most heat out of that diesel fuel to heat a camper than you do with
18:13
propane, which is cool because people in these groups have talked about the density
18:17
of the two, the propane versus the diesel,
18:19
which is like cool nerd stuff.
18:20
But they also talk about when you go into altitude,
18:23
how the altitude affects, how these burners work and how these little kits that
18:26
people have gone in and solve these problems.
18:28
So it's a real problem that people solve.
18:30
Same thing with generators.
18:31
People have generators. They go up in the altitude because the air is thinner.
18:35
They're generated and put out the performance they need and they have to get
18:37
a bigger generator to offset this or reset up the generator to work at that altitude
18:42
and then do it again and then get debt back down.
18:45
So the reason I'm talking about that even though it's off topic is it's relevant.
18:48
And if it's relevant to people that aren't engineers and scientists and professionals
18:52
that do that for a living, just people that do it on their own to figure these
18:56
things out, it's absolutely relevant to us who do this on a day -to -day basis.
19:01
And there's people that move all over the country.
19:03
You may live in this one climate and then you move to Vegas.
19:06
There's people that have moved from Florida to Vegas and understanding the difference
19:10
in the air and air weight and how that capacity works or somebody who finally
19:14
gets their dream to move to the mountains or moves from the mountains down the
19:17
sea level. These things all play a part.
19:20
They all act together.
19:21
So all these things we're talking about, we're talking a lot of numbers now,
19:24
but they're so important when you have the appreciation of what we're doing,
19:28
having an appreciation for seeing a psychrometric chart and thinking,
19:30
man, I don't understand this, but I want to.
19:33
So we're talking about these SCFM and the weight of air and how much heat we're
19:36
moving. It's awesome. It's really cool to think this has been mapped out for
19:40
us and it's been done and simplified to things like measureQuick so we can easily
19:44
communicate to that red, green, yellow dials telling us how many BTUs of heat
19:49
removing sensible and latent, how many pounds of water removing out of the air
19:54
every hour. The whole entire book of Psychrometrics Without Tears is pretty much
19:58
put into pictures and live data with measureQuick.
20:01
Yeah. And again, like, where does it matter?
20:03
It matters in a lot of cases.
20:05
As a technician, you're not going to typically do a ton of math,
20:09
but you need to know where to do the math when it's time to do the math and you
20:12
need to know how the tools basically do what they do and that's where you're
20:16
working at altitude. Remember to remember, remember to stop and be like,
20:19
okay, this is going to be different than when I was in Miami.
20:22
I'm going to need a little more air to do the same thing or my oxygen levels
20:25
are going to be lower when I'm doing combustion or whatever the case may be.
20:29
That's a good example of it.
20:30
But another really good example is if you're moving from markets where humidity
20:33
control isn't that big of a deal and then you move to a market like Florida or
20:37
you move to a market like Louisiana or areas in Mississippi or South Carolina,
20:41
areas that have a lot of latent load.
20:43
We're very concerned about moisture load in houses because we're trying to keep
20:46
people comfortable, but also really trying to keep suspicious growth from showing
20:52
up in different places.
20:53
I'm trying to learn my lingo here, suspicious biological growth.
20:56
That's actually what Florida wants us to say specifically.
20:58
They tell us suspicious biological growth.
21:00
That's the phrase because we want people to be healthy.
21:02
So we want to be comfortable and healthy.
21:05
And so the strategy that's been used for a long time and is still today is we
21:09
reduce that CFM per ton.
21:12
But what is it really?
21:13
We're moving fewer pounds per BTU.
21:16
And so if we think that we're running 350 CFM per ton but we're not taking into
21:20
account that derating of the equipment, we may actually be running 400 CFM per
21:24
ton when we're trying to run 350 because 350 to 325 is a typical target in our
21:29
market for good solid latent removal and sometimes even a little lower than that
21:34
for short periods of time.
21:34
You can get down to like 290 in some cases,
21:37
unintentionally in a lot of cases.
21:38
But here's where it gets interesting in our market.
21:40
And I was just like my favorite topic.
21:42
So just bear with me here for a second.
21:44
Is it the less airflow that you run over that coil,
21:47
the less pounds that you run per BTU,
21:49
the colder the coil is and the colder the discharge area is out of the top of
21:52
the unit. Well, that has other consequences.
21:55
Where is that unit located?
21:56
Is it located in a humid location where it's going to start sweating?
21:59
Okay, well, that can be a suspicious growth problem in and of itself.
22:03
Is the duct work going to start sweating?
22:04
Are the vents going to start sweating?
22:05
All of these different factors.
22:07
And so a lot of times with the way that we currently do it,
22:09
even to this day, we solve a problem because we're pulling more moisture out
22:13
of the house. But we create a problem by making ducts sweat,
22:17
vents sweat, unit sweat.
22:18
And what we've talked about a little bit lately,
22:20
just for fun because there are actually some people who design it this way is
22:23
you could really design systems where the airflow stays constant.
22:27
Meaning the amount of air that the blower moves through the vents stays constant.
22:30
And what you vary is the amount of air moving across the evaporator coil because
22:34
that's actually what matters in terms of moisture removal.
22:36
I actually saw that in your group chat that you had.
22:39
That's Michael Housh's brilliance.
22:40
I get blinders on.
22:42
I start looking at equipment.
22:43
So we're talking about manual T with Reagan and the vent throw.
22:47
And he's like, well, it doesn't matter because we have once we slow the flow
22:50
of air down, manual T is out the window.
22:51
And I'm like, I think it's important still because people don't appreciate the
22:55
throw at all. But it had a valid point.
22:57
And then Michael Housh has brought this up in the past.
22:59
And I forgot about it.
23:00
He's a brilliant man.
23:01
But you don't know him.
23:02
But he was talking about keep the airflow constant so that you don't have that
23:07
issue. Like, well, yeah, you keep the airflow constant.
23:09
You don't have to worry about the ductwork sweating.
23:11
But now you're not going to dehumidify.
23:13
And I'm like, it just obviously that's not going to solve the problem.
23:15
You're not going to dehumidify because I was thinking equipment and he's like,
23:19
no, obviously air bypass.
23:21
And I forgot he had the Frankenstein system where he designed it where you could
23:24
keep the air going to the coil separate decoupled I think is the cool word he
23:28
used from the rest of the air so he could keep his airflow up,
23:31
keep his volume up and still have the dehumidification factor.
23:34
And I was like, man, that is really brilliant.
23:37
It just brought me back out to the bigger picture of the house as a system.
23:41
But then it comes into like how we're going to make this repeatable and get it.
23:44
But that's how my brain works.
23:45
It's like, oh, this is a fun thing.
23:47
But then you can run down these rabbit holes.
23:49
But it's really awesome to think, hey, we want to slow the air down so that we
23:52
can dehumidify it. But keep the volume of air up so that we don't sweat in the
23:56
ductwork. And that's what I love about this trade.
23:58
There's never like, oh, just do this and we'll solve the problem.
24:01
Sometimes it will. Sometimes it creates a new problem.
24:03
And it's cool to have friends that educate you and get you thinking outside of
24:08
that box that I get stuck in sometimes.
24:11
Yeah. And again, because I remember the first time somebody brought this up to
24:14
me, this design, I saw it, somebody had specced it.
24:16
And I was like, oh, that won't work.
24:18
And I was like, wait, why won't it work?
24:19
And then I realized I was wrong because I was thinking like,
24:22
I don't know what I was thinking.
24:23
I was thinking it was going to like grow mold inside the ductwork or something.
24:25
But then you're like, oh, no, mixed air conditions.
24:27
No, this actually works just fine.
24:29
And the point isn't that because this is what I think a lot of people get frustrated
24:33
with me in the nerd community about.
24:35
You can be a purist where you're like,
24:37
if you don't know this, you don't deserve to carry tools.
24:39
And it's like, I don't think that at all.
24:41
And I think it's great guys who are early in their career and they just follow
24:45
best practices and they're learning as they go.
24:47
I think that's great.
24:48
You don't necessarily have to understand all this stuff in order to be a good
24:50
tech. But the more you do understand, the better problem solver you can become.
24:55
And so now when you run into this really weird situation,
24:58
a really tough situation where humidity becomes very important,
25:00
whatever the case may be, now you have an extra tool in your arsenal that you
25:04
know you can use to help solve that problem.
25:05
You understand it a little bit better.
25:07
That's where this comes in really handy.
25:09
If you live in Ohio and you're setting up equipment at 400 CFM per ton and you're
25:14
measuring it with TrueFlow Grid and you're going off the nominal capacity,
25:17
you're not doing all these derating conditions and all this,
25:19
you're probably not that far off.
25:21
It's not the end of the world.
25:22
It's going to be better than almost any.
25:24
But if you can drill down and you go to the expanded performance data on your
25:27
equipment, instead of saying four tons, you say 42 ,000,
25:30
43 ,000, 44 ,000 BTUs, whatever it is based on the actual rated conditions.
25:35
Well, then you're going to be a little bit better.
25:37
And then if you understand about air density and the difference between SCFM
25:40
and measured or actual CFM, you're going to be a little bit better.
25:43
You're just sharpening that knife a little bit more.
25:45
And it's not so you can be cocky and walk around with your chest pumped out at
25:48
the symposium and tell people how good you are with airflow.
25:50
That's not the point because it just makes you understand what you're seeing
25:53
a little bit more.
25:54
So I frequently talk with Chris Hughes and Steve Rogers.
25:58
And Steve Rogers is just brilliant a level that sometimes I can't grasp.
26:02
And then it's almost annoying sometimes.
26:05
He's like, it's like such a high level.
26:07
But then I want to feel smart too.
26:08
This isn't fair. But then Chris is able to like take that is like,
26:12
okay, let me translate this as a technician talk.
26:13
I'm like, all right.
26:15
And then we have these fun off the wall conversation.
26:18
Well, what if we did this?
26:19
And what if we did that?
26:20
And it's fun to exercise your mind and think outside of,
26:24
hey, we got the system back up and running.
26:26
When I first got into psychometrics, I was having so much fun solving problems
26:30
with psychometrics. I thought I was a superhero that was out doing stuff and
26:33
I had this one house.
26:35
The humidity was high in the house and the customer is blaming the equipment
26:38
and the guy with the equipment was like,
26:40
no, it's right. It's whatever.
26:41
So they were able to go through and find the capacity of the equipment under
26:44
the conditions that we had.
26:45
It's like, here's what it's performing.
26:47
Here's what it's designed for.
26:48
I ran my psychrometric chart, which does what measureQuick does automatically now.
26:52
We had to do this, but I did all the old school math.
26:54
Like, man, this thing is dehumidifying great.
26:56
We measured the airflow.
26:57
The airflow is down as low as it can go and we're dehumidifying like crazy.
27:01
So I had them call an energy auditor out.
27:03
They did a blower door test on the house because technicians didn't have that
27:06
available then. And they said, nope, the house is pretty tight.
27:09
Here's your leak points, et cetera, et cetera.
27:11
But with the outdoor humidity, wasn't really the problem.
27:14
So I came back out, crawled into the house and found there's a water leak.
27:18
So the water was leaking and coming up through the floor and that was where all
27:21
the humidity problems was.
27:22
So we were looking at all of these other things and the problem was outside of
27:25
the box. And so it's fun though when you start thinking outside the box and exercising
27:29
it, then you can solve more problems.
27:32
So we're thinking about airflow.
27:33
My big thing is, can you actually measure it?
27:36
And using the blower curves are nice, but only if it's a factory motor and the
27:40
factory wheel and there's some conditions.
27:42
There's a lot of other ways with using the hot-wire anemometer going in,
27:45
but people don't realize you have to actually traverse the ducts and do all the
27:48
different points, which is math.
27:50
And I don't like math because they get numbers mixed up.
27:53
But now we have the TrueFlow Grid.
27:54
And I realize a lot of people can't afford that.
27:56
I had to save up for over a year to buy mine.
27:58
So it was a huge investment, but it's probably the best tool I bought because
28:01
I could actually ideally quantify the airflow, check the airflow,
28:05
know exactly how much airflow I had with measureQuick.
28:08
I can find out what my system is doing and with the performance chart of the
28:11
system, I could find out what that system is capable of moving under those conditions.
28:15
And I can say, hey, I'm moving exactly what I'm supposed to and BTUs of this
28:19
airflow. BTUs, sensible and latent.
28:22
My system's good. Now let's look outside.
28:24
Duct leakage, house leakage.
28:26
What are my problems coming from outside of the equipment?
28:28
And it's fun being able to solve that,
28:30
but understanding airflow. Oh, just slow the blower speed down.
28:34
It'll solve all your problems or create a new one.
28:36
Now we have moisture happening in the attic.
28:39
Now the unit sweating like crazy.
28:40
And then somebody just tagged me recently is like,
28:42
hey, Ty, can you do a video explaining what this guy's problem was?
28:45
I was like, no, because I need to go out there or he needs to give me more information
28:49
because we can't just say the unit's condensating.
28:52
We need to do X, Y, and Z.
28:53
No, let's test. Let's get some data.
28:56
And with more information, I can make a better decision.
28:59
Yeah, and it does make it so much easier.
29:00
I mean, you can do and I actually suggest that at least a few times you do some
29:04
of these calculations longhand and all that.
29:06
I mean, it's perfectly good thing to do,
29:08
but nowadays we have tools and that's what measureQuick is.
29:10
It's an amazing tool to help us do the math and come to the right conclusions,
29:14
taking into account all these different factors.
29:17
TrueFlow Grid. Same thing.
29:18
Excellent tool. But yeah, you can get a test hotwire anemometer and do some measurements
29:22
there. I mean, you can do branches, so you can do other cool things.
29:24
It's really fun. I mean, I did a lot of that and it's a blast,
29:27
but you got to learn how to do it because it isn't straightforward.
29:29
It isn't just one measurement.
29:31
A lot of people are like, well, just take measurements with the flow hood.
29:33
It's like you'd be shocked how inaccurate flow hoods can be even.
29:36
So these are all things around measuring airflow.
29:38
If you want to learn more about this,
29:39
watch any of Bill Spohn's great presentations on airflow measurement.
29:43
TEC does a lot of really great presentations on this as well.
29:46
But go back to some of the old symposium videos and watch some of those because
29:49
we're not going to cover all that.
29:51
But the point here is, it is a bit of a moving target based on real site conditions,
29:55
based on the weight of the air, like we talked about,
29:57
versus just the boxes of air and based on the particular equipment and the actual
30:02
rated capacity of that equipment with all the factors included.
30:05
And some of those factors are variable with weather and some of them are not
30:09
variable. If you're up in the mountains, it's going to be in the mountains its
30:11
whole life probably unless somebody sells it used on Craigslist or something.
30:14
So it's going to be under the same conditions.
30:15
So set it up for those conditions.
30:17
If it's set on 208 power, in some cases,
30:19
not all equipment, but in some equipment, it does actually derate.
30:22
Not only it doesn't just change your current and your SEER rating,
30:26
but it also changes your actual capacity of the equipment in some cases.
30:29
So the motor actually slips more and runs a little slower if it's a PSC motor.
30:33
It's kind of wild.
30:33
Think about that. And so those are all factors.
30:36
Read again, all comes back down to reading the Fantastic Manual and being curious
30:40
enough to find out about the equipment.
30:42
But I'm really looking for it is, I don't know,
30:44
I think I told you this, August is my in the field month.
30:46
And this is one of the first things I'm really excited to do because at Kalos,
30:50
we use a ton of TrueFlow Grid grids now and I came out of the field before that
30:53
era. And so I'm excited to get out there and show everybody and learn myself
30:57
about all the different ways you can use it to find problems rather than just
31:00
we do it mostly on sales and some on commissioning now.
31:03
But I really want to get us doing it more because I think it has a lot of benefits.
31:08
All right. So NAVAC has some great vacuum pumps and hand tools,
31:11
but I'm also a big fan of their cordless power tools for bending,
31:17
flaring, and swaging copper quickly and easily.
31:20
NAVAC's three BreakFree power tools in their Power T3 lineup have all won ACHR NEWS
31:26
Dealer Design Awards.
31:28
And they've also won an award for me that I didn't publish that just says these
31:32
are great. The Bryan Orr, these are great awards.
31:36
Our techs use them all the time and love them.
31:38
The NTB7L power tube bender can help you create really high quality well-made
31:43
bends easily. There's seven size options with quick-connect mandrels letting
31:47
you bend tubing from quarter inch to seven eighths OD.
31:50
One button operation, just push a button and hold until you've got the bend you
31:54
want. Let the tool pop it out for you and you'll get a perfect bend up to 90
31:58
degrees each time. The NTB7L won gold for best hand tool in the ACHR
32:04
NEWS Dealer Design Awards in 2023.
32:07
The NEF6LM is their lightweight battery powered flaring tool.
32:12
Super light under three pounds easy to handle.
32:15
Flares copper in the standard sizes for residential and light commercial.
32:19
HVAC soft tubing quarter inch to three quarter and those flare dies are included.
32:23
Also just a quick note if you ever do have hard copper you can flare it so long
32:27
as you heat and anneal it so heat it up to where it gets dark cherry let it cool
32:31
off and then you can flare it.
32:33
All you have to do is prepare the copper lock it in press a button and let the
32:36
tool do the work for you.
32:37
You don't even have to hold the button you just press it.
32:40
And it won bronze for the 2022 ACHR NEWS Dealer Design Awards and the NTE11L
32:46
that is their power tubing expander often called a swedge tool comes with
32:52
quick-connect heads that fit most common sizes from three-eighths to one inch and
32:56
an eighth to swap them out depending on the size of copper you're using again
32:59
only about three pounds and this one also won gold for the 2022 ACHR NEWS dealer
33:05
Design Awards. Find out more about NAVAC's products and promotions including their
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power tubing tools at NAVACGlobal.com Riding with your guys is
33:16
boring because they care so much and they try so hard and they know a lot of
33:20
the stuff already so it's hard finding I have to go like do these weird things
33:24
to get them interested because they have so much of the other stuff down and
33:28
I'm used to going in like let me show you superheat like oh that's cool I mean
33:31
you solve those problems well you guys already know that it's refreshing right
33:33
it's refreshing knowing that instead of online somebody's saying you don't need
33:37
superheat or you guys embrace it and use it all the time it is nice if somebody
33:41
wants to start with us it's overwhelming all of these different things we talk
33:45
about where I recommend find a piece of equipment that you've installed find
33:49
an expanded performance data start just figuring out what all those numbers mean
33:53
don't let it overwhelm you just keep looking at it every day and you start seeing
33:56
different points and then say hey under these conditions get your wet bulb temperature
34:00
inside wet bulb temperature outside or dry bulb temperature outside and your
34:04
airflow and just start mapping out and then look and say hey what if I sped the
34:07
airflow up what would happen with my capacity if I slowed the airflow down what
34:11
would happen with my capacity if the day changed indoor and outdoor what would
34:14
happen and then once you start figuring out how that one works you can start
34:19
looking at different brands or different models and then you can start seeing
34:22
oh hey if I have three different brands here under the same conditions would
34:27
they have the same capacity then you can start to see that they don't and that's
34:31
what's cool is when you realize oh a three ton's not a three ton under different
34:35
conditions and it's fun and you start getting there really it's like the secret
34:39
like secret walls the secret text the secret things that people don't know you
34:42
start unlocking these secret things which is really what Manual S is all about
34:46
which like Tim De Stasio and I agree that the expanded performance data will
34:49
do what that Manual S is doing with just a shortcut on it yeah system selection
34:54
is a huge huge benefit of this thinking this type of thinking if you're in a
34:58
business where you're not doing any of that maybe you don't think about it but
35:01
if you ever do your own sales or your own specking of equipment like you said
35:05
I mean across brands even in things like ductless you can have some pieces of
35:09
equipment that have completely different capacities under rated conditions than
35:13
another under the same weather conditions and especially around latent if you're
35:17
in a market where you're trying to remove a lot of moisture you need to specifically
35:20
select your equipment for that not just at full capacity but also it turned down
35:24
because some manufacturers are taking that really seriously doing some neat stuff
35:28
around that and some are just ignoring it completely and just going for that
35:31
SEER number so there's a lot of things here once you start unlocking these little
35:34
power -ups of understanding you can start to do better in system selection and
35:39
commissioning and in service and that's the goal to be really really good at
35:42
all three of those and frankly thank you for the nice compliments about our guys
35:45
one thing about our guys is that they're just great humans they want to do the
35:49
right thing they really care very enthusiastic but a lot of them are very new
35:52
techs and they I wouldn't want them to select a piece of equipment they have
35:56
to get good at some of these other things first our sales team I still work with
35:59
them sometimes it's like why did you choose that a match over this match or creatures
36:02
of habit we're not always going to nail it but the more you understand this stuff
36:05
and the more you read the manual the better off you're going to be and I think
36:08
that's really the trifecta if you will you have to care you have to have good
36:12
tools and take good measurements in order to get a good result not that you can't
36:15
get an acceptable result it's easy to make people cold that's not hard but making
36:19
it really efficient or dehumidifies really well and does everything it's supposed
36:22
to do that's huge and then getting to the place that you understand it well enough
36:26
that you can really really set it up properly and choose it properly that's the
36:30
best situation because again if you're in middle America and your seasons aren't
36:35
that extreme compared to some other places you maybe can get away with it but
36:38
if you're in the mountains or if you're living in Florida or you're in the arid
36:41
desert of Death Valley you really need to know how to make these changes to the
36:44
equipment it's cool when you start testing it but also when we see that that
36:48
of those numbers for me numbers are just immediately give me anxiety and I have
36:52
to remind myself to calm down what's cool though is where those numbers came
36:55
from the story behind those numbers and when you get to go to some of the manufacturers
36:59
they have these psychrometric rooms where they can make the conditions at anything
37:03
that they want and they test every aspect of that equipment under those conditions
37:07
and then they record it and then they put it in this little graph for you so
37:10
when you see those numbers it's like oh it's just numbers but those numbers come
37:13
from people and equipment testing and for me like when I saw that firsthand I
37:18
was like that is really cool and I told the manufacturers why don't you guys
37:21
talk about this like let technicians know it's not just that we did numbers like
37:26
an engineer just came up with these numbers like you guys are testing this and
37:30
this room is amazing you can make it snow in this room and that's cool and like
37:34
oh we don't want anybody to see our psychrometric room like it's exactly the same
37:37
as all your competitors it's the same room you have the same room it's the same
37:41
AHRI testing points so talk about the show this but they don't and I have some
37:46
footage that I can't share because I don't have permission but it's really cool
37:50
when you see like where those numbers come from so if you ever get the chance
37:52
I know you have but talking to you guys in the field if you ever get the chance
37:55
to see a psychrometric room or a test facility it's absolutely incredible and
37:59
talk to the people that do those numbers and the work I mean like oh yeah we tested
38:03
this and we saw that and it's really fun to see where those numbers come from
38:07
it is funny and I also encourage you to out there if you're a decision maker
38:10
in a business reward the companies that publish really good data with your business
38:14
because there are some that do a lot better than others there are some who gate
38:17
keep a lot of that data and there are some who I in the past at least suspected
38:21
they may not have been testing the way they're supposed to there was one brand
38:24
that across all of their tonnage matches it was 18 seer and a particular brand
38:28
is 18 seer 18 seer I'm like no you're extrapolating you're taking one and then
38:32
you're extrapolating and you're not actually testing at all those conditions
38:35
but yeah most of the solid manufacturers that we all know do a pretty good job
38:38
of that testing but then getting access to that data is another question and
38:42
then us actually using it to our benefit and our client's benefit is that's the
38:46
main thing that's fun so 400 CFM per ton it's the scaffolding that can help us
38:50
understand some things but it's not the whole answer any final words man just
38:55
keep being curious keep learning if you find something that's overwhelming you
38:59
then dive into it if it's overwhelming or scaring you just go like full in on
39:04
it I'm going to learn everything about that for heat pumps I used to hate heat
39:08
pumps and I was like I had a guy say well what do you like about him and I told
39:11
him he's like sounds like you don't know enough about it I got mad it's like
39:14
oh yeah how do you tell he's like well go learn about it and come back and so
39:17
once I learned everything about heat pumps I was like this is stupidly simple
39:21
it's just like really simple I didn't understand it enough and then once I understood
39:26
it it's like okay well there's still some things I don't like and there's some
39:29
things I do like but now they understand it makes a difference so if we're talking
39:33
about something like this and it's like oh you don't need to know that I understand
39:36
that response I get that but also think man what if I just dive in and learned
39:41
everything about it then you could be like you don't need that and actually have
39:45
all the data points to talk about so I think it's a fun thing but what the key
39:48
is it's a trick because once you get into the numbers and seeing how all this
39:52
stuff affects what we do you get addicted to it it's like oh man what else can
39:55
we do with this what other problems can we solve yeah you get addicted to knowing
39:58
what's actually going on it's very frustrating to be a tech and not know that
40:02
and that's where we make a lot of excuses and do the whole like ah it's probably
40:05
fine it's like guilty once in a while oh, all the time I still do it I mean
40:09
like silly I the other day of my own system was a pound low something like that
40:13
and it had frozen up and I defrosted and just went and put a pound and didn't
40:17
leak check it didn't it's about right subcool's at 10 fine whatever so like
40:23
I get it and none of us are perfect at that but understanding how it works is
40:26
makes our lives a lot better and ultimately the result is that we get fewer callbacks
40:30
and we have happier clients and we actually deliver our promises better and better
40:34
it's not about perfection it's about progress and companies and techs who do
40:38
that well end up having happier customers in the long run it doesn't take a lot
40:42
to teach people how to change a capacitor but it does take a lot to fix homes to
40:47
fix the actual air so when you start out yeah you're changing apart and I've
40:52
made it run and that's great you did good but at some point you think if you've
40:56
only done that for 20 years and you're thinking you're still that's like your
40:59
whole thing think man what should I do to challenge myself to learn more and
41:05
air psychometrics how the system works is a great point to start but even better
41:09
if you're already young and you're like man I got these parts figured out I want
41:12
more I want more here's a great point to jump into it's exciting when you get
41:16
into this and that can unlock a lot more doors seeing technicians that get to
41:20
work for manufacturers and technicians that work for those representatives that solve
41:24
problems other people couldn't solve or go work in the psychrometric room so it's
41:28
interesting the doors that this can unlock in your future for sure Ty thanks
41:32
so much thank you big thanks to Ty he's
41:38
a great dude really is and it's good to have him here in central Florida at least
41:42
for the time being working beside us at our company Kalos Services he's with
41:47
the GRIT Foundation he has his own YouTube channel Love2HVAC and social media
41:52
follow him there but don't make him mad Ty is a lover not a fighter but he's
41:58
also a fighter so don't screw with him you know what I'm saying and why would
42:01
you want to anyway he's a great guy super cool dude again find out everything
42:05
that we're doing at the GRIT Foundation over at the GRIT Foundation dot com we
42:11
would always appreciate any support that you can provide and if you want to volunteer
42:15
you want to have a grit camp please reach out at the GRIT Foundation dot com
42:21
so I was talking to a country boy the other day he got upset because I wasn't
42:25
using the right pronouns he said his pronouns are he ha he
42:34
should be yee ha I'm not sure he ha that's pretty old school anyway thanks for
42:38
listening we'll talk to you next time on the HVAC School Podcast