Let's discuss the manometer, so you're asking: why do you have the two ports from one port we're reading pressure in the duck? The pressure in the duck has more pressure than in the room right this system's in the room. We have a fan mechanically pressurizing with air. The plenum it has pressure right, but what do we measure that pressure against? How do we set the bar and say what is that pressure? We need to reference it to something right and that's where the second port comes into play. This port doesn't have a hose.

This port is saying: here's the pressure here. So what's the pressure in what's the pressure in the duct in reference to the room, does that make sense? So what if you had horizontal out of attic application, would you have to run a hose to the indoor room or no you're in the attic and the attic's vented right? Normally? Hopefully, this application so addictive you're you're, basically dealing with outside pressure at that point. So you don't have any pressures and you're referencing that pressure, i'm not sure if you would come into a situation where you have enough pressure in the room that would be so drastic where it would cause an inches of water column and balance on that input. But you can use this gauge for room pressurizations if you wanted to so here's a nice application with this tool, let's let's just for a second step away from the digital truffle and you buy the kit that comes with the dg8.

And let's say you got a house: that's got a massive master bedroom right, huge two exterior walls vented attic a lot of heat coming in from the attic, let's say the insulation and see older house it's r, 20 right and it's not placed well right. You got two walls, they're full of heat, a lot of glass and they also got that massive bathroom right, congrats and there's a huge. You know huge garden, tub four by four window, massive eight inch drop in the bathroom or something right. What i'm getting at is, let's say, there's 800 cfms going in that master, bedroom and bathroom combined, but all that air has to get back to the return right.

We got ta cycle the air, but let's say there's only one 36 inch door right there and it's got a one inch cut that problem yeah. It's probably my house, there's nothing in it, but um. I knocked out a 20 by 40 return to my kitchen and stuff, but it has so much pressure in that room that, if you walk by it like you, can hear the whistling from underneath the door right like literally it's the best thing in the world. Are we starving that air conditioner for air when we do that? Are we starving it? No, maybe right we don't know because we don't know if we're pulling air from outside in at that point.

Let's take a this is kind of getting a little deep, but let's say that room's heavily pressurized and the air is not coming back into the main room that air conditioner is going to get its air or the fan motor is not going to move in here. One of the two because it was a load-bearing wall, it was in addition, it was just a garage. Now it's a room. I did not seal the attic, so it is right.

So this is getting pretty deep into building science, but are we forcing potentially infiltration into the house at that point? Absolutely because what did we do? We've killed the conditioned air that we blew into the room, that's going to heat up and come back for re-circulate circulation, and now that are we do we have the chance of pushing that pressurized room air outside? No and yes, because i have single pane windows but there's leakage to a certain degree in every room right. So if we're pressurizing this room and it's heavily pressurized, do we run a risk of putting our conditioned air outside of that room? Yeah dude, that's gon na be perfect for you guys it's a mess and no insulation too by the way zero. So what i'm getting at is we can check room pressure from that room with the door shut in reference to the room, we're standing in. Let's say i'm standing in the main room that has a return, and i want to know if that room's pressurized because, let's say they're saying it's hot in this room at night: okay, well, a nice little quick test that takes two seconds: throw a tube under the Door shut the door at the pascals like you could switch this to pascal's.

If the pascals are saying 22., that's a heavily pressurized room right and that's a problem. That is a problem that coming in. But it's not going out right. Air is going in and they coming out we're starving the return or we're bringing air in from outside into the return, because we're forcing infiltration you put the positive tube in the room here and then leave that one to work right right.

So i think think of - and this i think by explaining this - it also helps you understand what we're doing with the pressure on the system right if that room's got more pressure than this room. Well, then, what's the pressure in that room in reference to the room? I'm standing in this would work well in commercial applications too. I would assume, as far as like restaurants, maybe um, especially in residence, but positive pressure, negative pressure. That's a big! Thank you, especially with makeup air.

Absolutely you you know in my previous life. I did a lot of uh grocery store air conditioning work. I wasn't on the refrigeration side and when you have those grocery stores, they have those massive kitchen hoods right and they're sucking out a lot of air and there's 80 80 makeup. But let's say they don't even have a dedicated outdoor air system and the build is negative.

Well, this manometer will tell you and outside in reference to inside. Is this build negative and if it is potentially you're going down the road of offering a dedicated outdoor system makeup air unit condition right same principle applies right, so it would be. It would be nice to start like really studying up on pascals, like it's a term that i feel like has not been addressed enough in the industry, but it's a very valuable measurement for years. I didn't know what pascals were right.

You know i'm not going to say i knew it five years ago it hadn't been too much smaller measurement of pressure. Right, like you would, with it's a powerful tool that i think we're just now in a large scale, starting to uncover that we can use this. For diagnostics, right, like microns micro parrots, just like it, that's the really nice part about the manometer. That's going with the kit right! You know because your typical field, banometer, is not going to read in pascals, so you're not going to be able to do that kind of stuff, you're right like not going to drop name brands, but you can't go into pascal measurements with typical 150 dollar manometers.

We want to focus on this one, so let me just explain what they are. This is looking at the airflow and the static pressures to get as much information as we can all in one here is, if you just wanted to do it even quicker, and only look at the flow, but not the pressures, and then this is actually, if you're, An energy rater and you need to do the system airflow for uh, resnet, 310 points. It's not you guys or in this one, if you're, just measuring pressure, just to look at the gauges, yeah so like. If you, if you measure, for example, pressure in a bedroom yeah - and you just want to save that, that's what that's working so you can tell exact room, you can go to each room and just use this one yeah.

So this this is a bedroom one bedroom! Two bedroom three and just save those as a just a pressure measurement so hit the top one there. So this is like. Is it a furnace or an air handling? Yep gas furnace yeah? So we got 270. You have uh 112, i think is the number.

This is a three ton, so what this is telling you is basically, when you set up the system, you want to make sure it's in the highest cooling speed. You want to make sure there's nothing, that's bypassing the filter. So if you had like a fresh air, a fresh air intake or a bypass filter, where somebody's like doing hepa as a bypass, you want to shuttle it off. So all the airflow is going through the main filter.

So that's just your setup screen. You can skip that after so now, we're going to start measuring pressures, we got the manometer here. Static pressure tip is on it. You just look at the photo and you put it where it says.

So, it's measuring a pressure. That's what you see here and you can go ahead and hit take a measurement. I wouldn't need two and put one like on the testo one i have to put both of mine in yep, but now on this one i can just put one in save the measurement yep and go to the next and move on, and then it's going to Calculate the drop so now, where you want to put it on the blower, i don't know exactly okay, how i would put it there, so i i actually let you mistake, make a mistake on purpose here. This is my filter.

That's supposed to be upstream of the filter, but in this case there's no ductwork upstream of the filter, so go back and change it to a filter. Grill go back, one more change that to a filter. Grill! Okay, now hit next okay. So now now there's it'll.

Only be one measurement yeah, it's a very unique uh application right here, yeah, it's a filter, grill disguised as a filter, slot yeah yep. So now it's telling you to put it between the furnace and the evaporator coil so that we've drilled a hole over on that side. I know this one here so between the furnace and the look at the diagram there. Are you pointing it down into the flow downwards there we go, you just hit, take a measurement, you got all three measurements you can either hit continue or if you feel like you made a mistake on one of those you could just tap on it and repeat, And retake it yeah or if you realize it's a two stage and you were running it, you know not in full blown dehumidification exactly and then you just hit continue yep.

So now you're actually going to take the filter out and put the true flow in, and that would be that yep, actually, it says, leave that there you want that needs to stay there. There i'll hold the door for you that'll be easier. Oh, you got a magnet yeah, it's a game, changer yeah! So is there a certain way this has to go or does it stay on it? I'm not going to tell you oh aaron wow. I was looking for an arrow yeah.

We have to put the arrow on the side. That's the problem! Okay, so that i mean as long as it's kind of set up, so that their air is not going to get past it yeah. Then you get you'll, get it all the way up yep. So when you take this measurement, it stays at the top going through everything.

Yeah we'll explain that later, but it actually needs to take this measurement with the filter and then it needs to take it again with a true flow in okay. So you put that in yep take measurement; oh it says it there. I like how you have pictures and like step by steps, but i like the pictures best, yeah, okay, hey those - are my best votes, comic books, man right, okay, so hit continue, so just give it a name. This is just how you want to save the file.

So there's what we got take a look there, so our total external static is pretty good. Yeah airflow is right on the border between being okay and being low too low. Okay, now look at down here. If you look at these three, that's going to give you some clues about, what's causing the flow to be so low, which is our mainly our return duck.

Yeah is our big problem yep. But what do you notice about this return back? I mean it's uh. So short, it's in air conditioning in this case. Do you think it's the 20 feet of flex? That's only 10 inch or do you think it's the filter? You know at this point um.

I would ask why he has this system in this warehouse yeah with another working system over there. Yeah right, i will be that guy yeah. So in this case we can probably assume it's not the flex duct. No, it would be a filter.

It's the filter, yeah right, so what we can do here, uh we made this handy dandy thing that we can take the filter out and measure with this instead and see how it changes things. Okay, last one - and now we get super fancy here. Have you put it in backwards yet uh with i song when they did it over there yeah it's nice to have this access, otherwise there'd be a little yeah. It's a little trickier in a real filter slot.

Where you, you can't grab the side of it yeah! Well, you'd also shut the unit off. Oh no, no, you wouldn't shut it up actually. Well, if the instructions say to shut it off, but in between, we know that people might not always do that if they're trying to keep it in high stage cooling. How durable are these things like if i drop it, because it's very durable okay, because i'm kind of clumsy we'll leave that in right, huh the instructions will leave that in i'll leave this one in i didn't follow the directions, it does say to turn it off.

I like how it has the step-by-step kind of you don't want to look at my phone. Oh look. I put it in backwards, see what happens. It was fun.

We were both watching you do it like yeah yeah yeah, i watched when they put it in backwards. You know 7 37.. All right. Everybody complains that they can't find the button it's just because they're not on team android jessica's not having that problem.

So in the apple version the continue button you just hit it's just tiny blue text. So now what do we have? And why so we've got that's good. First of all, the plenum: that's yeah, you've pegged the needle on the supply plenum pressure, so my airflow is too low because it's just kind of hanging out right there yeah, that's! Why that's on the red, just from the edge of the red and your total external static, is too high click on the details and that'll tell you what we think is going on undersized duck or blockage which is very accurate, yeah you, you hit the details, that's What that is yeah i was looking so i like that, because i you know, that's like on the the measure quick app and i use that so much that is nice. I like that and have you created a report before so click on the the yellow one? There you can actually take a photo of the uh camera, so that's gon na and it automatically saves them.

Yep so now hit create report and then scroll down there you'll see you're still putting them on there. But there's your photos, it doesn't pinch to zoom. You got to hit the plus button, but i like how it really breaks it down and when you're talking to the homeowner, it's black, they like black and white. So that's very helpful yeah thanks for watching our video.

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