# Whirlpool WMH31017AS User Manual

## Page 2

6" (15.2 cm) vent system = 73 ft (22.2 m) total

A B

C

D

6 ft (1.8 m)

2 ft

(0.6 m)

A. Two 90° elbows = 20 ft (6.1 m)
B. 1 wall cap = 40 ft (12.2 m)
C. 1 rectangular to round transition
piece = 5 ft (1.5 m)
D. 2 ft (0.6 m) + 6 ft (1.8 m)

straight = 8 ft (2.4 m)

3 " x 10" (8.3 x 25.4 cm) vent system = 73 ft (22.2 m) total

A. One 3 " x 10" (8.3 x 25.4 cm) 90° elbow = 25 ft (7.6 m)
B. 1 wall cap = 40 ft (12.2 m)

C. 2 ft (0.6 m) + 6 ft (1.8 m) straight = 8 ft (2.4 m)

A B

C

6 ft (1.8 m)

2 ft

(0.6 m)

A. Rectangular to round transition piece: 3 " x 10" to 6" = 5 ft

(8.3 x 25.4 cm to 15.2 cm = 1.5 m)

B. Roof cap: 3 " x 10" = 24 ft (8.3 x 25.4 cm = 7.3 m)
C. 90° elbow: 3 " 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 " 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 " x 10" = 10 ft (8.3 x 25.4 cm = 3 m)

A B C

D E F G

Rectangular to Round Transition for Roof Venting

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.

A

B

C

E

F

D

3" (7.6 cm)

A. Roof cap
B. 6" (15.2 cm) m

C. Elbow (for wa
D. Wall cap

E. 3 " x 10" to

rectangular to

F. Vent extensio

If the existing vent is round, a rectangular to round transition piece must be
used. In addition, a rectangular 3" (7.6 cm) extension vent between the
damper assembly and rectangular to round transition piece must be
installed to keep the damper from sticking.

Recommended Standard Fittings

A 3

¹⁄₄" x 10" (8.3 x 25.4 cm) rectangular or 6" (15.2 cm) round vent should be used.

The total length of the vent system including straight vent, elbow(s), transitions and wall or roof caps must not exceed the equivalent of 140 ft (42.7 m) for either type of vent.
For best performance, use no more than three 90° elbows.
To calculate the length of the system you need, add the equivalent length for each vent piece used in the system. See the following examples:

A. Roof cap
B. 6" (15.2 cm) min. diameter round vent

C. Elbow (for wall venting only)
D. Wall cap

E. 3 " 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) h

Because Whirlpool Corporation policy includes a continuous commitment to improve
our products, we reserve the right to change materials and specifications without notice.

Dimensions are for planning purposes only. For complete details, see Installation
Instructions packed with product. Specifications subject to change without notice.

Ref. W10609724A

11/12/13

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