Ductwork Calculations - GE PGP989 Owner's Manual And Installation Instructions

Calculate total Equivalent Ductwork length
Equivalent
Duct Pieces Length* x
6" round
straight 1 ft .
3 ⁄ " x 10"
1
4
straight 1 ft .
6", 90°
elbow 15 ft .
6", 45°
elbow 9 ft .
24" max .
flexible
metal offset
adapter 34 ft .
3 ⁄ " x 10"
1
4
90° elbow 16 ft .
3 ⁄ " x 10"
1
4
45° elbow 5 ft .
3 ⁄ " x 10"
1
4
90° flat elbow 18 ft .
6" round
to 3 ⁄ " x 10"
1
4
transition 7 ft .
Subtotal Column 1 =
* Equivalent lengths of duct pieces are based on actual
tests and reflect requirements for good venting
performance with any downdraft cooktop .
† Measure and list feet of straight duct used . Count and
list the quantity of all other duct pieces for the "Number
Used" of each type .
ImPortAnt:
For maximum efficiency, use the shortest and straightest
duct run possible, with as few fittings as possible .
For satisfactory performance, the duct run should not
exceed 100 feet equivalent length.
Venting performance is improved by using larger
diameter duct .
Installation Instructions

DuCtWorK CAlCulAtIonS

Number Equivalent
Used = Length
x ( ) = ft .
†
x ( ) = ft .
†
x ( ) = ft .
x ( ) = ft .
x ( ) = ft .
x ( ) = ft .
x ( ) = ft .
x ( ) = ft .
x ( ) = ft .
ft .
Duct Pieces
6" round
to 3 ⁄ " x 10"
1
4
transition
90° elbow
3 ⁄ " x 10"
1
4
to 6" round
transition
3 ⁄ " x 10"
1
4
to 6" round
transition
90° elbow
6" round
wall cap
with damper
3 ⁄ " x 10"
1
4
wall cap
with damper
6" round
roof cap
6" round
roof vent
Do not use flexible plastic ducting.
Vent installation should not exceed 100 feet
equivalent length .
20
Equivalent Number Equivalent
Length* x Used = Length
20 ft . x ( ) =
5 ft . x ( ) =
12 ft . x ( ) =
21 ft . x ( ) =
27 ft . x ( ) =
20 ft . x ( ) =
24 ft . x ( ) =
Subtotal Column 2 =
Subtotal Column 1 =
totAl Du CtWorK =
Should not exceed 100 feet .
ft .
ft .
ft .
ft .
ft .
ft .
ft .
ft .
ft .
ft .