York 251934-YTG-J-0910 Technical Manual page 103

ZJ/ZR/ZF180-300 Roof Curb Duct Openings
1. The 2" space between the ducts allows for "jumping" an
existing roof joist.
2. The 58-1/2" overall dimension of the ducts allows ductwork
penetration between roof joists that are spaced on 72"
centers.
NOTE: Ducts can be installed into the curb from the roof. All
electrical and gas line connections can be made inside
the curb.
ZJ/ZR/ZF180-300 Typical Installation
Johnson Controls Unitary Products
ZJ/ZR/ZF180-300 Cut Away of Roof Curb
Roof Jack
Installation
251934-YTG-J-0910
Roof Curb
Installation
Slab On
Ground
Installation
103