GE UVB30 Owner's Manual & Installation Instructions page 14

PREPARE FOR DUCTWORK
Determine the best route for ductwork; it can be routed
in a variety of ways depending on the kitchen layout.
IMPORTANT: The downdraft air discharge outlet
for this unit is 31⁄4" x 10" rectangular. Plan ducting
accordingly.
Typical duct arrangement countertop series.
To maximize the ventilation performance of the vent
system:
1. Minimize the duct run length and number of
transitions and elbows.
2. Maintain a constant duct size.
3. Seal all joints with duct tape to prevent any leaks.
4. Do not use any type of flexible ducting.
Install ductwork so the piece of duct nearest the
downdraft unit slots INTO the next piece of the duct.
Secure the joints with self-tapping screws and apply
duct tape around the joints to ensure an airtight seal.
14
Design Information
Optional duct arrangement under concrete
slab. PVC duct should be used if installing
under a poured concrete slab.
NOTE: PVC sewer pipe type PSM 12454-B
Schedule 40 ASTM D1785.
6" (15 cm)
Dia. 90
Metal Elbow
Wall Cap
6" (15 cm) Dia.
Metal Duct
12" 16"
(30 cm) (40.6 cm)
Max.
Min.
6"
(15 cm)
Dia. PVC
30'-0" (9.14 m) Max.
Coupling
6" (15 cm) Dia.
Pack tightly with gravel
PVC Sewer Pipe
or sand completely
Elbow
around pipe
Inside wall
cabinet
Up inside wall to roof or
overhang
Peninsula or island
Between floor joists
3-1/4" x 10" Rectangular
to 6" Round Transition
6" (15 cm)
Dia. Metal
Duct
Concrete
Slab
6" (15 cm)
Dia. PVC
Sewer Pipe
6"
(15 cm)
Dia.
PVC
Coupling
6" (15 cm)
Dia. PVC
Sewer
Pipe
6" (15 cm) Dia.
PVC Sewer Pipe
Elbow
Air
Flow
Screw
682Dia53
Outside
wall cabinet
Directly to outside
Peninsula
Through cabinet toe space
Duct Tape
Over Seam and Screw
49-80777-1