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How is outdoor air applied in OpenStudio?

asked 2018-09-22 10:43:24 -0600

JCR562 gravatar image

updated 2018-09-22 13:57:43 -0600

Hi all! I've got a few questions on how OA is applied in Open Studio.

If I build a system like an AHU with an airloop I know you can add an outdoor air system within the air loop. But if using a PTAC or DX Split System, is OA introduced by mixing with the RA stream before the coil?

Also, if I'm modeling a large apartment complex and each unit will have a dedicated small OA fan (20-30 CFM) do you think it would be acceptable to model this by creating one airloop with a supply fan, connecting it to the outside and applying a terminal diffuser to each zone?

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answered 2018-10-11 15:31:16 -0600

For ZoneHVAC equipment such as PTAC (packaged terminal air conditioner), fan coil, etc., outdoor air is mixed with return air in the unit. DX split systems are typically modeled as an airloop system.

For the large apartment complex application, yes, a single airloop to provide OA to multiple zones should be identical to multiple single-zone OA units.

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Thanks MJWhite, much appreciated.

JCR562 gravatar image JCR562  ( 2018-10-14 18:00:58 -0600 )edit

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Asked: 2018-09-22 10:43:24 -0600

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Last updated: Oct 11 '18