topic Re: VAV Units CFM information on the Properties dialog... in Revit MEP Forum

VAV Units CFM information on the Properties dialog...

Anonymous — Mon, 09 Dec 2019 14:44:22 GMT

The VAV Unit that I am adding for an existing HVAC Ceiling Plan that is being prepared with Revit, and which come with the program, has under the properties dialog's "Mechanical-Flow" a Primary Air Flow of 900.00CFM which is grayed and cannot be changed there, another one has 1400.00 CFM, etc, (all the numbers are grayed) but the numbers on the schedule of the old plan that I am using for the new prepared numbers have different CFMs.

Where do I change these CFM numbers so the VAV boxes that I add to the plan have the correct numbers?

Thanks in advance.

Re: VAV Units CFM information on the Properties dialog...

RobDraw — Mon, 09 Dec 2019 14:50:11 GMT

The CFM of the VAV is determined by the air flow of the properly connected diffusers.

Re: VAV Units CFM information on the Properties dialog...

hmunsell — Mon, 09 Dec 2019 16:54:06 GMT

select a VAV family and navigate to the Mechanical - Flow > Air Flow parameter. on the Right hand side of the parameter is a small box. select that and see if it is being associated to another parameter.

Re: VAV Units CFM information on the Properties dialog...

Anonymous — Wed, 11 Dec 2019 14:10:12 GMT

I can select the VAV model in the 3D and it gets blue, but the number under the Mechanical - Flow and the Primary Air Flow is grayed and I do not see the box that you mention to its right. I see the box in other lines, like in the Primary Air pressure line, and in the Plenum Air Pressure, but not in the Primary Air Flow, so I assume that something is locked somewhere that would not show the box.

Thanks for your feedback.

Re: VAV Units CFM information on the Properties dialog...

RobDraw — Wed, 11 Dec 2019 14:17:19 GMT

Did you see my response? VAVs do not have an assigned flow. It is determined by the connected diffusers.

Have you tried that yet?

Re: VAV Units CFM information on the Properties dialog...

hmunsell — Wed, 11 Dec 2019 15:03:26 GMT

can you send an image of the Properties and Type Properties windows showing the parameter?

Re: VAV Units CFM information on the Properties dialog...

RobDraw — Wed, 11 Dec 2019 15:07:30 GMT

Hello...?

The correct CFMs should be there when the diffusers get connected to the VAV with ducts.

Re: VAV Units CFM information on the Properties dialog...

Anonymous — Wed, 11 Dec 2019 15:36:53 GMT

Thanks to all, I am learning with you all.

If anybody wants to provide a little info about how the Justify tool is used, or a link on how to use it with instructions, please advise.

Re: VAV Units CFM information on the Properties dialog...

RobDraw — Wed, 11 Dec 2019 15:43:08 GMT

New topic should have it's own thread.

How about staying with the current topic until it's solved?