Hi, i'm brian with hvac school podcast and hvc our school comm, making this video today in conjunction with true tech tools about the testo 420 flow hood. So I'm going to go over some basic steps for using a flow hood in general and then some features of the 420. This is a photo of the 420 right here. I've got one right behind me: I'm going to show you how we set that up.

First thing to know about the 420 is is extremely light. It's just over six pounds. It's got a great price point. It's got a really large tilt table display and actually it's a removable manometer that you can actually use to take Pido to measurements.

If you wanted to use that for taking pitot tube measurements as well, it also the testo 420 also connects to a bluetooth app so that you can use that to take all of the readings in a particular space and format them into a report which is another Nice thing, so you can use it for taking spot to spot ratings. You can also use it to make a larger report for an entire structure. So let me show you how this works alright. So this is the test.

O 420 got the got the flow straighteners right here. You can see them a little bit better. As I open it up. You can see the flow straighteners that helps make sure that, when the air flow is coming into the flow hood, that it straightens it out and doesn't have a lot of turbulence, because anything that happens with the air flow where it goes in and bounces off.

The walls it doesn't hit the pitot array down at the bottom straight that can affect your reading, so I'm going to show you real quickly how to put this together. It's really really easy. We have these dashed lines in here that show you where you want to assemble the poles. So what what you do? Is you just pull it out straight? Put the poles in there's little receivers in here they go inside the poles, so there now you can see that it's all assembled and the flow straighteners have straightened right out nice and easy.

So this is the large display. It's really really nice easy to read, display it tilts up and down turn it on. You just hit the power button in order to take a reading. You just hit this red button here and then that holds the reading in the display.

So if I were to hit it, it would hold. Obviously, there was no no reading because there's no air flowing, but when I take a rate measurement, I just hit that and says hold and then, when I'm ready to take my next reading, I just release it and now it's reading again. So there's always some air flowing in a space like this, so it's not surprising that you'll get some small readings. One thing you will notice with this flow hood and with most flow hoods is that they do have a minimum and maximum range.

This flow that is going to read accurately down to 50 CFM, plus or minus, and so, if you have very very small events, say a bathroom vent in a small bathroom, that's producing 30 CFM! It's going to be difficult to measure with this. I would go ahead and use a vein anemometer in order to read, instead of using the flow hood in an application with very low flow. But the fact that this goes to over 2,000 CFM means that in most applications, this is going to be a great option. Now you can use the flow hood for a couple different things you can use it in order to measure all of your diffusers, then add them up to get total system airflow.

You can also use it to compare against a set of plans. So if you have some specs or plans that show you what your design CFM output is, you can use that for test and balancing even in residential applications. It's a really good idea. Obviously, every diffuser every register has a designed CFM output and so by going making those readings and doing some balancing adjusting your balancing, dampers you're, going to get a much better result.

I understand that that's not a very common thing in most residences, but it really is a good idea and then obviously, commercial test and balance is a little bit more complicated a longer process, but the tests go for twenty supports all of those purposes. This guy back here this guy right here - this is Sean - is our estimator salesman extraordinaire. But what do you like to be called? So this is the test. Oh 420 flow hood in its cases comes in a nice case.

It's called a flow straightener and so the flow straightener. What it does is is it captures the airflow as it comes in and it helps to straighten it out. So you don't get turbulence going down the sides. It's one of the kind of unique features about the 420 and it is proven to make it more accurate because a lot of guys think well flow hood flow.

That's going to give you an accurate reading, no matter what, but actually it won't necessarily because, as the air goes in, especially the airs direction, a little bounce around it will create eddy currents and really where everything reads is now here at the bottom. In this pitot tube array, so down at the bottom of every every flow, hood, there's a pitot tube array and that's actually where the reading takes place. When you initially set up the device use you go into will go back to the beginning. Here you go to display and then you're going to want to set your volume flow to CFM your differential pressure to inches of water column, your temperature to Fahrenheit so just sitting here in the room, because there is some flow in the room you, you may read A few CFM s here and there and that's to be expected and it'll change a little bit from room to room which you know you do need some velocity of flow for it to read accurately and that's true of any device.

There's a threshold of where it will read accurately and where it will not read accurately with this device. You really kind of need to get it over 50 CFM for it to four to give you an accurate, read, let's go ahead and put it into let's go ahead and put it into Bluetooth mode. You just hold it on up hold down this UP button. You see the little Bluetooth icon is flashing now, so now we can connect to the application to find device there we go so we have this device to connect to.

We are now connected to the device in single measurement mode. You can see these small changes in inches of water column are what provide us our CFM reading, and this I can go through and actually check. I can actually see the trends of the readings. I can read a table of all the readings at different intervals.

As you can see here, you to header configuration in settings and you can set up all your company information, you can add a logo. All that kind of thing you can even import a contact. You want to import a contact for the customer and then that will go into your flow report, because you can actually create a report either on the device or on the app. If you look on the device here, this is where you would go in and create the report.

So you can. You can read one at a time to your different measurements. Alright, so we've got an eco, be thermostat here, and you may there's a couple different options when you're testing air flow. What you really the best way to do it is to put the system into high stage cool so that that way, you're running your maximum air flow and in most cases whatever setting, is your maximum air flow.

So I've got an in test mode here and then disconnect the condenser so that that way, your air density isn't going to be affected by the changes in temperature over time. So I've put it in high stage cool I'm going to go out to the condenser and pull the disconnect alright. So the first thing about the about the test, oh, is that it's really really light. I mean it's lighter than its pretty much industry-leading as far as weight and the other nice thing is.

It's got these swivel handles, which is nice when you're transferring from this position to kind of this position. If you, if you're reading something that's far overhead, you really should be able to do 10-foot ceilings without a ladder with this, which is a just a nice feature, so we're reading 117 CFM in this configuration. Let's see what we read if we change the configuration 103 104 106, this direction 104 103 - the other direction. So you always have to give it a couple seconds to let it sit in all right, so I've taken it out of Bluetooth mode so that I can use the actual button on the on the device.

So we get 98 CFM and hit the button that holds it once I hold it, then I can take it down and read it. Assuming then break my customers house, and then I hit the report button here and then it says, save that value I hit OK and now that saves that value into that report. So that's how I go one at a time through put it up, hit the button that holds it. Then you hit the you hit this document button and ask you if you want to say that you save it in the report and then you can keep going and then later on.

When you connect to the app, then you can pull the full report. That's probably the most practical way of doing it. So now we're going to go into the next minute and again, each time I'm going to check it. It a couple different configurations just to see if turning it 90 degrees changes the reading.

If it does change the reading, then we need to kind of think about the exact position of the vent. Try it a couple different ways and maybe even average. So let's say I'm getting a significantly different reading in this configuration in this configuration. Well then, I might measure it the other direction as well and then see then average out the readings in order to what the best position is.

What the best reading is, the one you don't mind if I knock the popcorn all off your ceiling, all over the place for you, you know what it's something we had an hour to do this. Okay, that's good! Very agreeable! One is a very agreeable customer, so the other nice thing is, you, don't necessarily have to see it as long as you hold it up there for five seconds, so we're going to say 1, 2, 3, 4, 5, and then I hold the button, which I can't Find them I hand the right place so now I hit the button that holds it to 99 CFM and it's not currently on hold right. Now, I'm turning it into another configuration just to check hold it again. Now you can see we're reading 99 or 98 CFM.

So we're reading 98, we were, we were reading 99 before so we feel pretty good about that. Read 99-98. It's a good reading! So we're going to now go ahead and hit the document button. It's going to ask us if you want to save the value we hit.

Okay and now it's saved in the report. So now we're ready to keep going we're going to go ahead and lock that one end right there. So 48 CFM is a pretty good average of what we're reviewing. So now, I'm going to take this out of here, so I don't knock over any of one's priceless paintings.

Do the bad thing with this Clos head? Is that I'm not really getting a workout and that's why I like my old al Moore's, it's a lot heavier and I feel like I'm really working on my biceps. This thing just doesn't give me the umph, I'm looking for all right, so we're reading Edie 79. In that range, okay, so first we've got to hit the UP button so that the Bluetooth comes on. The device shows up actually that this feature works pretty nice.

It actually shows up pretty easy now, once it connects, then I'm going to go into the memory. We're going to select this folder, and these are all of the these are all of the readings so I can do. Is I select all of the readings that I took they're all selected, and now I have a report that I can that I can configure. I can go in and edit it.

I can add images. I can add comments for every particular reading as a place for I can sign it. I can print it. I can do all that kind of thing you see here.

I can edit the customers information. It's a really really nice report. If you wanted to do like a full balance report for me, I'm just using it to keep track of the different readings that I took. So I can do the math, because some of the some of the events I wasn't - I wasn't able to get on with the flow of it anyway, so I'm going to have to use a vein anemometer for those alright.

So, in order to further demonstrate this, we're going to use this to take our measurement on a commercial supply register. I got my technician Mike here manager manager, Mike any any of you have any time now. We can probably yeah all right I'll figure it out. Just uh just put good notes in the call all right there.

What do you have just waiting you, you ready now yeah now ready, okay, good trick commentary on the weight. It's like how much would you guess that it weighs if I hope you guys with this wave, I say in eight point five pounds wrong just over six, because yeah, I would think as a fisherman. You would know this kind of thing, mmm, all right. So as you places that over we're going to show it on the app so now we're going to hit play all right so just hit play so that we're actively reading what does it say on the screen? Can you see it 179? 182? You can see it reading the same thing here, so if we want to log this reading, we just hit pause.

So now that reading is locked in then we go here and that saves the reading, and now we can take our next reading and add it all to the report pretty easy that easy Mike, very good. Thank you! That's it. I'm Brian or testo 420 flow hood. You can buy the test.

Oh 420 flow hood or find out more information by going to true tech tools. Comm, that's t, ru tech tools, comm all one word. If you'd like to find some more videos, you can do that here and, if you're interested in purchasing the testo 420. Here's a link for that.

Thank you for watching.