18 - Air loops with water coils

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´╗┐Hi everyone. This is Harshul Singhal again. In this class, we are going to cover more stuff on HVAC related components. In our last class we talked about air loops, we created a simple VAV system with DX heating and cooling coil. Now, for this class, we are going to do some things, some new things.I'm going to show you how to remove the existing components, how to add new components,and later, I will also show you how to create a plant, sorry, a water based HVAC system. We'll create a new air loop, which will have a hot water and cold water coil. And, they will be connected to some plant loops with heating boiler, with chillers, with condensers, all right. In my last class, we created this loop, what you see on my screen. In case you need to delete some components, how do you do it? Like, for example, I want to remove this setpoint manager. I will select it. Go to my right hand side. Let me just bring more information, here. I don't know, I don't know why I don't see it here, okay. Like, if I, if you click on this tiny triangle, here. Click on it. And then, it will give you the option to delete this set point manager. Delete this.

If you want to delete this existing cold water,I'm sorry, single-speed DX coil, you can just select it, and click on this tiny cross mark, here. Same with this heating coil. If you want to delete the outdoor air controller, if you want to delete fan, as well. And, what if you want to remove some zone, the existing zones.What you can do, you can either select this splitter, or mixer, here. And, just uncheck these options here, uncheck these zones from this list. And, now we have this empty loop, air loop. It doesn't have any components. Now, what I'm going to do is, I'm going to create another system, here. I will just flow with the waves.I'm going to add some new stuff. We'll go through my library and see if I can create some interesting HVAC loop for you, okay. From the library, the first thing that I'm going to bring is one outdoor air controller, outdoor air system. Outdoor air system is here, you can see it, here. Air loop HVAC outdoor area system. Drag it and drop it on this node, the existing node. You can rename it now. You can rename it later. First of all, I want to click on this dotted line, and I'm going to rename it properly, I don't like this name.

I'm going to rename itVAV-WaterBasedSystem, let's say. It's a very long name, but yeah, let's just give it something unique, okay. Because, this is going to be my primary system, I'm not going to size it for 100% outdoor air in heating and cooling. If it's a DOA air system, dedicated outdoor air system, then yes, you need to size it for 100% outdoor air in heating, as well as in cooling, okay. For now, rest of the values seem fine. This you can see, here. Even the type of load to size on, is sensible. If it's dedicated outdoor air system, then you need to select a ventilation requirement, okay. Next thing, what I can bring is, I can bring one fan. Let me just bring a fan, here. Maybe a variable fan, variable speed fan. Drag it, and drop it on this node, here. And, what if you have one variable fan, even at demand side? Let's just drop it, here. You can see,it's not allowed here. A lot of times people think that you can drop these components anyway, but it's not possible. A lot of components, they just belong to supply side. Even,let's say, in an unique system, you have one fan at demand side, in real life systems. What you need to do is, you need to simplify your project. You need to bring one fan only at supply side, okay. But, what if you have one fan after this outdoor air controller? Can you bring it here? I think yes, see.

Now, the next thing that I want to bring is one cooling coil. This cooling coil is going to be water-based. I need to look for a coil cooling water, bring it, here. Drag it and drop it. Do you want to bring it before fan or after fan,it's totally up to you, it's your system. For this,I'm going to bring it after fan. Drag it here, and drop it. And, the next thing that I need to bring is one hot water coil. This is here,it's here. Let's bring this hot water heating coil. There are a lot of components. I created some of them for my own projects. As I mentioned to you earlier, you can always create your own library and save it. You might not even see all these options, but like, even if you bring any of them you can always edit them, okay. I have fan, I have outdoor air controller, I have hot water and cold water coils. Next thing that I want is set point manager. Let's bring a new kind of setpoint manager this time. What if we bring a dual setpoint, set point manager, drag it and drop it. If you click on this setpoint manager, it basically controls your high setpoint, as well as, low setpoint schedule. Which means your temperature, the schedule, or the water, which is coming out of this pipe here, it will vary between these two values, okay. Like, for example, if I want to check these properties here, the min/max temperature versus deadband max and min temperature schedule. The names are quite long it seems. These are default names, again. You could always edit them. These are my two schedules. You can see my default for max temperature is 80 degree, and for minimum is 50. The water that comes out of that air loop will vary,I'm sorry.I'm sorry, it's totally my mistake.

The air that will come out of that air loop to supply side will vary between 50 degree and 80 degrees Fahrenheit, okay.I'm sorry, again, it's air loop, not water, that's my mistake. If I go back to my HVAC systems, again, and click on this VAV water based system. Now, I need to bring something for demand-side, okay. For demand-side,first of all, I need some diffusers. There are different kind of options for diffusers. Let me just show some of them, here. You have duel ductVAV, you have single duct uncontrolled VAV with no reheat, inlet side mixture,you have parallel induction units, as well, okay. Why don't we bring parallel induction unit this time. Or, maybe chill beam, let's bring chill beam this time, okay. If I bring chill beam here, or, you know what,let's start with something simple, here. Let's bring VAV with reheat, for now. Because,I'm going to show you chill beams and PIU units in my next class. Let's bring this hot water reheat, again. Drag it and drop it, here. And, very important thing, click on it, go to this linkage, here. Here on top right, click on this linkage. You can see it doesn't show you any connection, here. It doesn't give you any option to connect this heat water coil to any hot water plant. Why? Because, we don't have any plant loop for now. We're just going to, like, you know, keep it as it is, for now.

First, what we are going to do is, we are going to create one plant loop. Because, what will happen eventually, we want to reduce our workload, guys. If you don't connect this VAV reheat box to any water coil. What will happen if we have 10 or 15 diffusers, later,VAV reheat diffusers. We need to reconnect those diffusers to plant one by one. If you just connect this existing reheat diffuser, right now, with one plant loop, and just keep bringing new stuff, you need not to connect all those new ones to your plant loop again, okay. I'll show you what I'm trying to say, here. I mean, I know it's a bit confusing. But,let's just go to this plus sign, again. Create this plant loop, this is the first time that we are working on plant loops, so just stand with me, here. I'm just going to click on this, add to model, option. And, you can see this like, plant one. Let's go back to VAV water waste system,and click on this diffuser, and see if it allows you to connect to this new plant loop, the empty plant loop that I created just now. See, it allows you to create, to connect to this plant loop.

Let's just connect it to this empty plant loop. I know I'm going to rename this plant loop 1 to hot water plant loop. I will bring heater, there. I will bring pump, as well. But, for now, let's just connect it with this empty plant loop, now, for now. And, click on this mixer, here.I'm going to bring some thermal zones to this VAV water based system air loop. Just connect some of the thermal zones, here. Let's say, just floor one. And, you can see, all these diffusers, they are created by OpenStudio, automatically for you. Even if I click on this,let's say,VAV hot water reheat to diffuser, and go to this linkage. You can see it is connected to plant loop 1. And, that's what I meant when I told you earlier that, hey, just connect one diffuser to 1 plant loop, or one hot water coil, or, plant loop for that. And, it will automatically bring that linkage for you, for the rest of the diffuse, of the new diffusers,okay. It reduces your workload this way. Click to all the floor one thermal zones. Rest of them are floor two or floor three. And now, once you are done with this VAV water-based system.