Table of Contents
Advertisement
Available languages
Available languages
STEP 2:
PREPARE THE VENTING SYSYTEM
STANDARD FITTINGS
NOTE: If the existing duct is round, you must use a rectangular-to-round adapter, with a rectangular 3"
extension duct installed between the damper assembly and the adapter to prevent the exhaust
damper sticking.
DUCT LENGTH
The total length of the duct system, including straight duct, elbows, transitions, wall or roof caps must not
exceed the equivalent of 140 feet.
For best performance, do not use more than three 90 degree elbows.
Below are the standard fittings and their equivalent length in feet.
1
4
90˚ elbow
To calculate the equivalent length of each duct piece used, see the examples below.
For 3 1/4"x10" SYSTEMS
3 1/4"x10"
90˚ elbow
2ft.
1-3 1/4" x 10" 90˚ elbow
1-Wall Cap
8 feet straight duct
TOTAL LENGTH
2
3 1/4"x10"
3 1/4"x10" roof
to 6"=5ft.
cap=24ft.
5
3 1/4"x10"
wall cap
=40ft.
=10ft.
Figure 9
Examples
6ft.
wall cap
=
25 ft.
=
40 ft.
=
8 ft.
=
73 ft.
— 9 —
3
3 1/4"x10" 90˚
elbow=25ft.
6
7
3 1/4"x10"
flat elbow
45˚ elbow
=10ft.
=5ft.
For 6" ROUND SYSTEMS
90˚ elbows
2ft.
transition
1-transition
2-90˚ elbows
1-Wall Cap
8 feet straight
TOTAL LENGTH
wall cap
6ft.
=
5 ft.
=
20 ft.
=
40 ft.
=
8 ft.
=
73 ft.
Advertisement
Table of Contents
