George,
The 90' connector is not allowed for the reasons others have already listed.
My problem is why are you letting anyone put a junction box in a cold air return ???
300.22 (C) Exception; is in the book because a stud or joist space is NOT other space but is a duct or plenum covered by part (B)
Alan--Inspector
[This message has been edited by Alan Nadon (edited 11-07-2005).]
