Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question
1

VRF outputs in OpenStudio

asked 2016-09-23 16:46:58 -0600

clguen's avatar

updated 2020-01-27 18:45:49 -0600

I'm modeling a VRF system with a DOAS using the VRFwithDOAS HVAC whole system measure.

Under the zone equipment detail in the OpenStudio Results nothing is showing up for sizing.

image description

This is similar under the zone report (OpenStudio Measure). It doesn't appear as if the VRF heating/cooling coils are auto-sizing. Although it looks like the fans are.

image description

There aren't many unmet hours. However, I'm not convinced that the load is being picked up by the VRF coil. It could be picked up by the DOAS.

Is it common for VRF coil sizes to not show up properly in the OpenStudio output report?

Any direction would be helpful. Thank you.

edit retag flag offensive close merge delete

Comments

Could you please make a separate post for each question so they are easier to search for? These are both good questions that I have had before.

kramerica's avatar kramerica  ( 2016-09-26 09:38:37 -0600 )edit
1

I created a second question. See: EnergyPlus output variables in OpenStudio

clguen's avatar clguen  ( 2016-09-26 10:40:02 -0600 )edit

Do you have design days in your model?

mdahlhausen's avatar mdahlhausen  ( 2016-09-26 11:08:40 -0600 )edit
1

In the standard report, at a minimum the name of each component will show. For each HVAC component type that we wanted to show additional information, we have to hand code logic on what to show. In some cases there are decisions we need to make about which or how many characteristics to show. The coverage is not comprehensive, so we certainly could update or could take contributions from others who wan to update the logic for additional components. Air loop and plant loop detail follow similar logic. I can add VRF to list to add next time the measure is changed.

David Goldwasser's avatar David Goldwasser  ( 2016-09-26 12:13:45 -0600 )edit

I do, mdahlhausen.

clguen's avatar clguen  ( 2016-09-26 12:20:16 -0600 )edit

That would be great David

clguen's avatar clguen  ( 2016-09-26 12:20:27 -0600 )edit

A few more questions - do your zones have thermostats, and are you seeing heating and cooling in your model? Does the VRF sizing show up in the energyplus results (NOT openstudio results)?

mdahlhausen's avatar mdahlhausen  ( 2016-09-26 15:49:44 -0600 )edit

I am able to find the "Design Size Gross Rated Total Heating/Cooling Capacity" for the Coil:Heating/Cooling:DX:VariableRefrigerantFlow under the Component Sizing Summary for the Entire Facility. The coils are not listed under the Equipment Summary, but the VRF fans are.

I have a heating and cooling set point schedule applied to the zones under the thermal zones tab.

clguen's avatar clguen  ( 2016-09-26 16:18:29 -0600 )edit

One last question - do you have the "Do Zone Sizing Calculation" checked in your Simulation Control tab under Simulation Settings in OpenStudio? Can you upload and post a link to the model?

mdahlhausen's avatar mdahlhausen  ( 2016-09-26 16:50:06 -0600 )edit

Yes, "Do Zone Sizing Calculation" is checked. Where do I upload the model? I'd appreciate the help.

clguen's avatar clguen  ( 2016-09-26 17:25:33 -0600 )edit

1 Answer

Sort by ยป oldest newest most voted
2

answered 2016-09-26 09:41:31 -0600

For your second question, you can add output variables in OpenStudio with the OS measure "AddOutputVariable" under the "Reporting -> QAQC" measures. You then type in the output variable name similar to how you would in IDFEditor.

edit flag offensive delete link more

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Training Workshops

Careers

Question Tools

2 followers

Stats

Asked: 2016-09-23 16:46:58 -0600

Seen: 1,291 times

Last updated: Sep 26 '16