Discover how to effectively modify and adjust Variable Air Volume (VAV) systems for optimal airflow in specific rooms. This article provides a step-by-step guide on how to alter duct sizes, create openings, and position the VAVs correctly to ensure efficient control of airflow.
Key Insights:
- The article guides on how to install VAVs on both the first and second floor of a building for optimal airflow in each room. This involves creating an opening in the duct, deleting unions, and setting the VAV at the right height.
- Adjusting the duct sizes is a critical step in the process. The author recommends deleting the connections before changing the duct size to ensure uniformity and efficiency. This can be achieved by trimming the ducts together or changing the diameter of multiple ducts at once.
- After installing the VAVs and adjusting the duct sizes, the author suggests making the duct system more efficient by reducing the size of the duct after giving away for two diffusers. This can be done by splitting the duct and adjusting the height of the connection as needed.
Note: These materials offer prospective students a preview of how our classes are structured. Students enrolled in this course will receive access to the full set of materials, including video lectures, project-based assignments, and instructor feedback.
In the previous video, we went ahead and got some more supply diffusers put in, but we actually kind of forgot one critical thing, and that is going to be to put in the VAV for these here. If you do get the project not saved recently, just go ahead and save project so you save your progress as you go. So what we want to go ahead and actually end up doing is we actually need to throw some VAVs on both the second and the first floor for these particular rooms.
So I kind of have my windows tiled. Let's get this back into kind of a normal orientation. Sometimes it can get a little jarring when I've got a plan over here and a plan over here.
So I'm going to go view. I'm going to go tab views. There we go.
Now I see my entire second floor mechanical. We want to be using a VAV, so I'm actually going to create a spot for it. So I'm actually going to split SL, this duct.
I'm going to kind of give an opening there. Delete. There we go.
%20(1).png)
Learn Revit MEP
- Nationally accredited
- Create your own portfolio
- Free student software
- Learn at your convenience
- Authorized Autodesk training center
And then I deleted the little, it puts in some unions and where that is split. So I'm going to make sure I delete those also. So I'm here in the, in this, in the second floor here.
So I'm going to go up to my systems. I'm going to go mechanical equipment. Let's go ahead.
VAV. Let's see here. We want to go ahead.
The VAV. Let's go with the 10 inch. There we go.
We need to bring it up. I'm going to go ahead and bring it up to 11 feet for right now. And there we are.
Boom. We have the 10 inch in and then the 14,12 out. And we'll make these duct sizes.
Correct. So sometimes when we're adjusting duct sizes, what I like to do is I like to delete the connections. The reason being is that if I change this to just a 10 inch duct right now, if I go here to 10 inch, notice how it puts, it keeps this the same size.
Now I could take this and change it to 10 inch also. And there we go. So, or what I can end up doing is I can just delete this, change these to 10 inch and then trim it together.
And it gives me the same thing. And I believe you should be able to just select all three. There you go.
You can select all three and change them all to 10 inch. In some instances, because this is duct in duct fittings, you can go ahead and do that. But in some instances with certain items, you may not be able, once you select a different category or something, notice that you do not have that option available to change the diameter here, because this obviously doesn't have a diameter setting.
We've made that a 10 inch duct. Now this I'm not 100% sure it's in the right place. I'm basing the middle of this duct at 11 feet.
I'm taking this guy, this is at 11 feet, but this is probably from the bottom of the union unit, not the center line of the duct. So let's bring your section over. And there's a couple of different ways that go about this.
I'm going to bring this section over. Let's go in there. So you can see the bottom of my VAV unit lines up with the center line of my duct.
There's two different ways I can go about this. I can go ahead, I'm going to drag this out. And I created a duct connection off of that.
And then I can change this. Now if I change this, let's say if I just change this to 11 feet, it's going to move the entire unit, which is kind of what I want to, I can also use my align tool. And then I could also if I wanted to, in the plan view, if I go back to this, I could take this guy, change it to 11 feet here.
And then it should update you just don't see it because it's moving up and down in a view that we're looking up and down. So sometimes I always like to confirm that these are aligned. And then I go ahead and just trim it together.
There we go. I'm going to go ahead and take this guy and I'm actually going to make it a smaller duct. We don't need the 16 inch.
So I'm going to make this a 14. There we go. And then here I can go ahead that's at 11 feet there.
Let's see, can I drag it to that connection? And it looks like I'm good. Let's double check it in the section. Everything looks great.
We kind of forgot to add in that VAV, but it's very easy to come back in and adjust the VAV as needed. What I can go ahead and do is I can go ahead and slide this down. And remember the VAVs are kind of what control each independent room, if that makes sense.
We have the VAVs so that a thermostat in this classroom controls the airflow to this classroom, so on and so forth. So that's why we put VAVs in every single classroom. So I'm also going to go ahead and adjust this duct system a little bit.
I don't really need this to be the 14 inch after I've already given away for two of the actual two of the diffusers. So I'm going to go ahead and split it right here. And what I can go ahead and do is I can take this down.
Let's go ahead and take it down to a 12. There we go. And if I wanted to, I could take this guy and just, you know, maybe be more efficient with the system.
Take this guy down to an eight inch, because that's going to be the tie in to that one there. Great. Let's go to the first one, do the same thing.
So I'm going to go to my ceiling mechanical. I'm going to split the duct here to give a spot for my VAV. Delete the portion that I split, delete the two unions.
Then I can go over to my systems mechanical equipment here. It should be the same VAV. So I want to go ahead and make sure it's oriented the right location.
The right orientation pick here, I'm going to do my little 10 inch out. I'm going to grab that. And I'm going to adjust that elevation.
So you can see it's the 11 and six and six and three eighths of an inch. Change that to 11 feet. That's going to move my unit down.
I know that that's 11 feet. I know this is 11 feet. We're good.
I'm also going to go ahead and make this duct size a little bit smaller. So I'm going to select all these pieces here. I'm going to make this my 10 inch duct.
And there we go. I can just take this drag and there we are. And we're good to go.
Now from here, I'm going to go ahead and make this my 14 inch duct. There we are. I'm going to go ahead and slide this guy down to that connector.
Perfect. We're going to go after the two, I'm going to split this guy here. I'm going to make this one a 12 inch duct.
And if I wanted to change this union, if I wanted to move this, I could just grab this transition. And I could say I wanted it to be like directly after the diffuser. I can go back to there if I wanted to.
And then the same thing here, split. And we'll make this an eight inch. And there we go.
Again, you can adjust the location of this of this transition as needed. Perfect. There we are.
So let's go ahead and now kind of do the same. We currently have this larger 16 inch duct, but we want to go ahead and as it goes down, we want to reduce it. So I'm going to split here, I'm gonna start at the end because I know that this is going to be like an eight inch connection.
This here has a 12 × 12 connection, so on and so forth. We can go ahead and make this guy a little smaller. If I make all these eight inch, boom.
And let's hope we have another little transition here, I guess. We got a couple of different transitions here. There we go.
So you may want to take a look at in 3D. So here, what I'm going to go ahead and do is I'm going to split it up here. Once it gets up here, and let's go ahead and make this just 12 inch.
And there we go. We've started to kind of clean up that system a little bit, make it a little nicer. I'm going to go to my level two.
I can go ahead and split here. And what I could also do is let's say I just wanted to be able to adjust those ducts. I can go select, I'm dragging a window over the left to right.
And I could use my filter option, I could remove air terminals because everything else I'll be able to adjust the diameter of. And it didn't want to do it. That's okay.
Sometimes it wants to work out that way. Let's see here. Oh, it's probably because I have this union up here.
Let's see if I remove that union. No, didn't want to do it. That's okay.
What I'm going to go ahead and do is I'm just going to work through it as I need to make sure we get all the pieces. Eight inch. And there we go.
Perfect. I'm going to go ahead and split this up here. I'm going to make this guy a 12 inch.
So depending on what you select, sometimes it'll allow you to do just change the diameter up here. Probably had some, maybe something extra or a type of fitting that didn't allow for that kind of adjustment. And there we go.
We've gone ahead and finished out the bathrooms, the exhaust and the supply system. The supply system, we tied into our existing air handler unit. The exhaust system, we went ahead and put in a brand new fan, routed all the duct and adjusted the ductwork.
Great work. We'll see you in the next video.