Why three duct connectors in fan powered terminal units?

[tim99]

I don't get it. In manufacturer's content for fan powered terminal units, the manufacturers I have seen, and even the fan powered terminal content from Revit, includes an unused duct connector on the plenum inlet of the fan powered terminal units.

Don't get me wrong, I understand fan powered terminal unit design and operation.

The air systems I design use the cooling load design air flow as the dictating air flow for duct sizing and equipment selection, so therefore in my fan powered terminal unit families I do not plan to put an extra duct connector at the plenum inlet.

Is there something I will mess up by doing this, or...maybe I should say by not doing that?

Thanks.

[david.vanslyke]

Not everyone does that.

Check out the fan-powered ATUs from METALAIRE --

http://www.metalaire.com/BIMLibrary.aspx


They show an area for the plenum inlet, but there's no connector on it.

If you're not going to be attaching duct, you really shouldn' th ave a duct connector there. These guys at least seem to know that.

[tim99]

Thank you. I needed to double check that was ok to do...or in this case not do.