Learn HVAC Tutorial: Using the Web Application
Overview
The Learn HVAC Learner Application (client application) is only one piece of the puzzle. The companion is the Web application which you have already logged onto in order to download the software.
If you signed up with a guest account, you will not be able to access the more advanced features of the Learn HVAC Web App which will be covered in this tutorial. You will need to create a new account as sign up as an Instructor (We are in the process of implementing an upgrade account feature, but for now, you will just have to create a new account).
Once you've logged in, you are presented with a Dashboard which tells you how many scenarios you have created. On the left, you can see the options available to you; you can view Your Scenarios, view Your Classes, or visit the Community Directory. Let's start in Your Scenarios.
Scenario Basics
Here you can view the scenarios you have created. Go ahead and click the Create New Scenario Button.
When creating a new scenario, first you will be asked to fill out general information about the scenario. Name, descriptions, and goals are all for your own benefit and the benefit of your students.
The second field, Master Scenario, asks you to choose a master scenario from which the defaults of your scenario will be loaded. You can then alter these below. At present, only Grand Master is valid, so choose that.
Scrolling down:
Difficulty is also for you own benefit. The number does not affect the scenario itself, but provides you and your students with feedback on how difficult you expect a scenario to be.
Inputs Visible, Inputs Enabled, Faults Visible, and Faults Enabled all do nothing right now. Just ignore them
Scrolling down more, you have these options:
Long-Term Simulation: You can specify the start and stop date for the long-term simulation analysis. You can also allow your students to choose their own timeframe and overwrite you simulation dates if you want by checking the checkbox below. The date format is Year-Month-Day, so 2010-01-01 is January 1st, 2010.
Real-time simulation: This is where you can set the start time for what is refered to as the short-term simulation in the Learner Application. You can choose the date and hour. Like with the Long-term Simulation, checking the checkbox at the bottom will allow your students to overwrite your settings.
The Allow students to view Heating Coil and Cooling Coil Valve Information will show or hide their values from students.
Allow students to view the debug window button.
Allow all users to view this scenario: This will allow other people to have access to this scenario so they can use it for their own classes. Currently, this sharing is only open to all users. In the near future, we will allow you to restrict who will be able to view your scenarios so you can share then with colleagues, but not the general population for example.
Now you've set up the basic parameters of the scenario and should have a screen like Figure 5-7. You can edit these parameters by clicking the green Edit Scenario button in the upper right.
Changing Scenario Variables
Now that you created the basic shell of a scenario, you can edit specific variables to teach students about the interaction of different components. Click on the Manage Variables Tab.
In Figure 5-8 you are presented with a long list of variables which you can modify. First, let's look at the table header and just navigating this long list.
The first column is a checkbox so you can easily select multiple variables at once. The All Button in the header allows you to select everything.
Index: This number represents the order in which a variable is sent to, or received from the simulation engine. By clicking the Index header, you can sort the variables by their index number—a quick and easy way to located a specific variable if you know the index number
Component: This tells you which HVAC/Building component each variable is a part of. You can filter the variable table to show only variables associated with a specific component. Simply click on the drop-down menu, select a component—for example, Room—and click the Filter button on the right side of the table. To clear it, just click the Reset button below the Filter button, or click on any of the headers titles.
Name: the name of the variable which is hopefully decipherable as to what piece it is. Clicking the Name header will sort in alphabetical order.
Disabled: This is a simple Boolean, true or false, telling you if the variable is active or not. Like with the Component, you can sort using this field by clicking the drop-down menu and then hitting the Filter button.
Type: Similar to Component, you can sort based on what type of variable it is: Input, Output, or Parameter.
- An Input is a variable which you or the user can change the value.
- An Output is a variable which the simulation will store/change the value.
- A Parameter is a like an Input, but is treated as a constant by the simulation engine.
When it comes to filtering variables, all of the Headers with drop down lists can be combined for more specific filters. For example, select VAV Box for the Component, select True for Disabled, and Parameter for Type and then hit Filter. You should see a list of variables like in Figure 5-11.
The final column under the Filter and Reset buttons, show a Pencil and Trashcan icon. The Pencil allows you to edit a specific variable. Go ahead and edit the top variable.
Here, you can alter all the aspects of the variable, such as its value, range, units.
Name: Your name for the variable which will be used by the simulation engine.
Display Name: This will be the name shown to the Learn HVAC user
Description: This is a description of the variable which will be displayed in the information button in Learn HVAC. See Figure 5-12
Component: Which component this variable belongs to.
I/O Type: Input, Output, or Parameter; see above for description
Index:
Unit SI: a string displaying the units in International Standard. Example: m/s or degree C
Unit IP: a string displaying the units in Imperial Measurements: Example: f/s or degree F
SI to IP: the conversion equation from SI to IP; Example: for degree C to degree F: (SI * 1.8) + 32
This table contains a list of some of the standard Units and conversion equations currently used by Learn HVAC:
| SI | IP | Conversion |
| kg/s | GPM | SI*15.88 |
| C | F | SI*1.8+32 |
| W/C | Btu/hrF | SI*1.895 |
| m3/s | CFM | SI*1765.7 |
| W | Btu/h | SI*0.2931 |
| Pa | In.W | SI/249.1 |
| kg/s | C | SI*1653.46 |
Low Value: Lower bound of acceptable entries
High Value: Upper bound of acceptable entries
Initial Value: Default or starting value
Notes: Notes for yourself
Fault Information
Fault checkbox: Check if it is a fault; it will then show up in the Fault tab in Learn HVAC.
Fault Active: check if it is on by default. Otherwise students will have to click it to turn it on.
Fault Widget Type: This controls the user interface for the fault. Choose "SLIDER" or "CHECKBOX". A Slider might be better when there is a range of values the fault can have, whereas the Checkbox would just be On vs Off.
Disabled: If checked, the fault is shown to the user, but greyed out so they can't edit it.
Subsection: A group label under which to put this fault. For example, if five faults have this value as "VAV Damper" they'll be grouped under a subheader called "VAV Damper" Left Label: Text to display on the left side of the fault if it's a slider
Right Label: Text to display on the right side of the fault if it's a slider
Zone Position: Where to position the center of the color gradient inside the slider. Values are "LEFT" "CENTER" and "NO_GRADIENT"
Is Percentage: this is just whether the value for the variable is a percentage. The slider will show 0% - 100% if it is
After making any changes you want, you can save the changes by clicking the Update Scenario Variable or Create Scenario Variable if you are making your own variable.>
The final part of a scenario is Managing Access. If you chose to make the scenario available to the public, then the screen will just say that the scenario is Public and the scenario information can be viewed by any user in the system. For more information on what other users can view, see the Community Directory section below. If your scenario is Private then you will see a screen like in Figure 5-13.
This particular screen skips ahead a little bit. You will see no group listed and only your account under people. Once you go and create a class and invite students in the next section, then that class will be listed here under Group, and all the registered students will appear under People, just like in Figure 5-13
If you want to remove a particular student's ability to access a single scenario, you can click the trashcan icon next to their name. This will prevent them from accessing that single scenario, but they will still be able to access the other scenarios which make up that class.
Creating a Class
Once you've created some scenarios, the way you distribute them to your students is by setting up a class. To set up a class and manage invited students, click on Your Classes, then click New Class
Now Name you class, click the Scenario you want to share with your students. To select multiple scenarios, hold the Ctrl button while you click. Then hit the Create Group Button.
Once the class is created, an invitation URL will be displayed which you can email to you students or place in your syllabus. Students following the link will be presented with a page like in Figure 5-16 where they can sign-up.
Alternatively, you can send them an email by clicking on the Online Form. Simply enter their email addresses separated by a comma.
Returning to your class, either by clicking the My Class Tab or going back to the Class Dashboard and selecting the class you created, you can view the Students who have signed up by clicking Members. If you want to remove a particular student from the class, simply click the trashcan icon next to their name. Clicking on their name will bring up a Community Card with their name, contact information, and institution affiliation
Community Directory
The final component to the Web App is the Community Directory. Here you can connect and learn from others using Learn HVAC. Click Community Directory on the left side of the screen to access it. You'll see a screen much like in Figure 5-19. If you do not see the View All links at the bottom of the screen, then expand the screen down until you do (just another strange bug we are working on). As you can see, you can view the Institutions which users represent, and individual users. For both individuals and Institutions, you can view the shared scenarios assosicated with them. Go ahead and click View All for People and browse the users who have registered for Learn HVAC. When you see someone who has a shared scenario, click on them.
Once you click on a user, you'll see a card like in Figure 5-20. To view their scenarios, click on their Institution Name.
To view more about a shared scenario, click on it and you will be able to view the settings for that scenario. To view the variable list, click Variables.
This list of variables is just like the variable list you were presented when creating a scenario.
