If the equipment is going to be based off of the same ceiling level, then you should use the same Reference Plane (or Level) to host them both. As I mentioned previously, Ducts must be associated with a Level, not a Reference Plane.
River Itchen. The River Itchen is a beautiful chalk stream which flows for approximately 28 miles from mid-Hampshire to Southampton.he source of the Itchen is situated in Cheriton, near Alresford, and flows down to the historic city of Winchester passing through nature reserve Winnall Moors, and Winchester City Mill.
River Test. The River Test is a river in Hampshire, England. It has a total length of 40 miles (64 km) and it flows through downland from its source near Ashe to its estuary at Southampton, where it converges with the River Itchen to form Southampton Water. In its upper reaches it is a chalk stream, and is used for fly fishing for trout.