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

How to model VAV system with no return air?

asked 2017-11-14 17:37:17 -0500

anonymous user


updated 2017-11-20 12:41:51 -0500

I have been playing around with the minimum and maximum outdoor air parameters but it does not seem to have any effect. How can I model an air loop that suplies conditioned air and does not have any returns or recirculation? I was tried adding the Always On Discrete schedule but it does not seem to work.

edit retag flag offensive close merge delete


Assuming you are using EnergyPlus, for the Always On schedule, are you applying that to "Minimum Outdoor Air Schedule Name", "Minimum Fraction Outdoor Air Schedule Name" or both? Also when you say it doesn't seem to work, does that mean you are not getting any outdoor air, are not getting enough, or are only getting it at certain times? Might be nice to include text from entire Controller:OutdoorAir object.

David Goldwasser's avatar David Goldwasser  ( 2017-11-16 11:50:23 -0500 )edit

1 Answer

Sort by ยป oldest newest most voted

answered 2017-11-16 20:55:27 -0500

TomB's avatar

Try to apply the answer to this question to your case.

I think you will find it difficult or impossible to model no return air explicitly. However, a 100% outside air system is effectively the same thing.

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


Question Tools


Asked: 2017-11-14 17:37:17 -0500

Seen: 196 times

Last updated: Nov 16 '17