11
VENTING DESIGN SPECIFICATIONS
This section is intended for architectural designer and
builder/contractor reference only.
NOTES:
■
Vent materials needed for installation are not provided with
microwave hood combination.
■
We do not recommend using a flexible metal vent.
■
To avoid possible product damage, be sure to vent air outside,
unless using recirculation installation. Do not vent exhaust air
into concealed spaces, such as spaces within walls or
ceilings, attics, crawl spaces or garages.
For optimal venting installation, we recommend:
■
using roof or wall caps that have back draft dampers
■
using a rigid metal vent
■
using the most direct route by minimizing the length of the
vent and number of elbows to provide efficient performance
■
using uniformly sized vents
■
using duct tape to seal all joints in the vent system
■
using caulking compound to seal exterior wall or roof opening
around cap
■
not installing 2 elbows together, for optimal hood performance
If venting through the wall, be sure that there is proper clearance
within the wall for the damper to open fully.
If venting through the roof, and rectangular to round transition is
used, be sure there is at least 3" (7.6 cm) of clearance between
the top of the microwave oven and the transition piece. See
“Rectangular to Round Transition” illustration.
Rectangular to Round Transition
NOTE: The minimum 3" (7.6 cm) clearance must exist between
the top of the microwave oven and the rectangular to round
transition piece so that the damper can open freely and fully.
Recommended Standard Fittings
The following length equivalents are for use when figuring vent
length. See the examples in “Recommended Vent Length.”
Roof venting
Roof cap
Wall venting
Wall cap
A. Roof cap
B. 6" (15.2 cm) min. diameter round vent
C. Elbow (for wall venting only)
D. Wall cap
E. 3
¹⁄₄
" x 10" to 6" (8.3 x 25.4 cm to 15.2 cm)
rectangular to round transition piece
F. Vent extension piece, at least 3" (7.6 cm) high
A. Rectangular to round transition piece: 3
¹⁄₄
" x 10" to 6" = 5 ft
(8.3 x 25.4 cm to 15.2 cm = 1.5 m)
B. Roof cap: 3
¹⁄₄
" x 10" = 24 ft (8.3 x 25.4 cm = 7.3 m)
C. 90° elbow: 3
¹₄
" x 10" = 25 ft (8.3 x 25.4 cm = 7.6 m)
D. 90° elbow: 6" = 10 ft (15.2 cm = 3 m)
E. Wall cap: 3
¹⁄₄
" x 10" = 40 ft (8.3 x 25.4 cm = 12.2 m)
F. 45° elbow: 6" = 5 ft (15.2 cm = 1.5 m)
G. 90° flat elbow: 3
¹⁄₄
" x 10" = 10 ft (8.3 x 25.4 cm = 3 m)
A
B
C
E
F
D
3" (7.6 cm)
A B C
D E F G
