Heatilator BIR42 Owner's Manual page 50

66 in.
(1676 mm)
HX4 Hearth Extension
1/2 in.
(13 mm)
ID6 Insulated Duct
6 in. (152.4 mm) i.d.
42 in.
(1067 mm)
UD6 Uninsulated Duct
6 in. (152.4 mm) i.d.
42 in.
(1067 mm)
20 in.
(508 mm)
DFG4042 Series Glass Doors
DFS4042 Series Screen Doors