How are HVAC templates applied in HB/OS? They don't appear to match default Eplus templates

One of our energy modelers reviewed the idf files generated by Honeybee/OS and noticed a few issues. I’ve copied her comments into several posts, 1 per item.

#7: HVAC Templates

The following is the Eplus template found in C:\EnergyPlusV8-3-0\ExampleFiles for packaged VAV. It includes Minimum Outdoor Air Schedule, Night Cycle Control, Cooling Coil Setpoint Reset Type and an option to turn on the return fan. We noticed that the models generated through HB/OS do not have some of these items input. How exactly are HVAC templates applied in OS and why do they not match the Eplus templates? Does choosing some options versus others trigger these or is there additional measures to include the above strategies while generating the energy model in ladybug tools?

SchoolsFirstOffice.osm (724.7 KB)
in.idf (613.1 KB)

@LelandCurtis ,

All of those controls can be added within the OpenStudio interface (or with OpenStudio measures) and some of them (like the outdoor air schedules) can be added with either the “Set EnergyPlus Zone Schedules” component:

The reason why a supply air temperature reset and return fans are not included by default is because the code baseline systems do not have these features. Oftentimes, if I need to account for these, I find it easier to model supply air temperature resets by putting a humidistat in the zone (so that they air is super-cooled when it’s humid) and I raise the default air loop supply temperature like so:

I tend to account for exhaust fans by just adding their pressure rise to the pressure rise of the supply fan:

But, as I said, you can add them into your exported model using the OpenStudio HVAC tab if they are important to your project and you need higher accuracy results.