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Air Inlet Node and Air Outlet Node are missing

asked 2016-03-18 10:03:33 -0500

Morteza gravatar image

updated 2016-03-18 11:23:07 -0500

How can I assign Air Inlet and Air Outlet Nodes to the model? This is a midrise apartment project so I have selected PTAC with HW heating for the baseline model. I also have created a hot water loop and an air loop (following screen shots) but when I run the project, encounter following errors:

Error detected in Object=COIL:HEATING:WATER, name=COIL HEATING WATER 1 * ~~~ * Field [Air Inlet Node Name] is required but was blank

Error detected in Object=COIL:HEATING:WATER, name=COIL HEATING WATER 1 * ~~~ * Field [Air Outlet Node Name] is required but was blank What is the solution? Thank you for your time,

image description C:\fakepath\Air Loop.jpg

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answered 2016-03-28 15:26:25 -0500

It looks like in your case, you dragged a Hot Water Coil onto the Plant Loop, but this coil is not inside of a PTAC or attached to an Air Loop. I would try deleting the coil then following these steps to add a PTAC:

  1. On the Thermal Zones Tab, drag a PTAC from the library into each zone image description

  2. Click on each PTAC

    1. Click on the Chain Link icon in the upper right
    2. Click the check box to connect the PTAC to the Hot Water Loop (which you've already created) image description
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Thank you so much for your help. I was not aware that OpenStudio would automatically add a hot water coil for each PTAC. After the extra coil was deleted, I was able to run the simulation without any error. Is there any limitation to the number of PTAC in each project? In another word, is this process would be okay for a mid-rise apartment building with more than 200 residential units, that would have more than 200 PTAC systems and hot water coils?

Morteza gravatar image Morteza  ( 2016-03-31 17:19:19 -0500 )edit

No, there is no limit to the number of PTACs you can have, but your simulation run time will increase. Once you get the settings for one PTAC set up as you like, you can select all of the zones you want to copy use the "All" column, click the PTAC, then click "Apply to Selected" to copy this PTAC to all the other zones. This is faster than dragging in each one manually.

aparker gravatar image aparker  ( 2016-04-01 10:19:05 -0500 )edit

Thank you, I truly appreciate your time.

Morteza gravatar image Morteza  ( 2016-04-04 17:57:36 -0500 )edit

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Asked: 2016-03-18 10:03:33 -0500

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Last updated: Mar 28 '16