Outdoor Air Flow Rate Fraction Schedule

asked 7 years ago

updated 7 years ago

I am curious about the function of the "Outdoor Air Flow Rate Fraction Schedule" under "DesignSpecification:OutdoorAir" of space type. (I use OS 1.13)

The inputoutput reference file shows that this field will defines how outdoor air requirements change over time. However, I test a few models with different schedules but results didn't show any difference. What is the function of "Outdoor Air Flow Rate Fraction Schedule"? What output will it affect?

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did you make sure that your terminal units have the "Control for outdoor air" checked to "yes"?

mdahlhausen's avatar mdahlhausen  ( 7 years ago )

@mdahlhausen, no, should I make it "Yes"? I don't want each terminal unit controls zone OA exactly, just want to make sure total OA in AHU OA controller match my design

Yan's avatar Yan  ( 7 years ago )

If you don't check yes, then your terminal units will not be controlled for Outdoor air. Maybe this is what you want. You can set minimum outdoor flow rates for the system level, with a schedule, in the Controller:OutdoorAir object in the AirLoopHVAC tab.

mdahlhausen's avatar mdahlhausen  ( 7 years ago )