GE PVWS936 Duct Fittings, Installation Instructions, Flexible ducting, 1 Ft = 0.3 m 1” = 2.5 cm

Installation Instructions

DUCT FITTINGS

Use this chart to compute maximum permissable lengths for duct runs to outdoors.

Note: Do not exceed maximum permissable equivalent lengths!

Maximum duct length: 100 foot for vent hoods.

Flexible ducting:

If flexible metal ducting is used, all the equivalent feet values in the table should be doubled. The flexible metal duct should be straight and smooth and extended as much as possible.

Do NOT use flexible ducting.

Note: Any home ventilation system, such as a ventilation hood, may interrupt the proper flow of combustion air and exhaust required by fireplaces, gas furnaces, gas water heaters and other naturally vented systems. To minimize the chance of interruption of such naturally vented systems, follow the heating equipment manufacturer’s guidelines and safety standards such as those published by NFPA and ASHRAE.

Using a smaller diameter duct size will reduce performance

			Total
	Equivalent	Quantity	Equivalent
Duct Piece Dimensions	Length*	Used	Length
	1 ft.
Round,	(per foot
straight	length
	1 ft.
3¼” x 12”	(per foot
straight	length
90° elbow	8 ft.
45° elbow	6 ft.
3¼” x 12” or	15 ft.
90° elbow
3¼” x 12” or	9 ft.
45° elbow
3¼” x 12” or	20 ft.
90° flat elbow
7” round to
3¼” x 12”	1 ft.
transition
3¼” x 12” to 7” round	5 ft.
transition
7” round to
3¼” x 12”	5 ft.
transition 90° elbow
3¼” x 12” to7” round	15 ft.
transition 90° elbow
Round
wall cap	30 ft.
with damper
3¼” x 12”
wall cap with	30 ft.
damper
7” round	30 ft.
roof cap
Round	24 ft.
roof vent

1 Ft = 0.3 m 1” = 2.5 cm

*Actual length of straight duct plus duct fitting
equivalent. Equivalent length of duct pieces are
based on actual tests conducted by GE Evaluation
Engineering and reflect requirements for good
venting performance with any ventilation hood.	Total Duct Run

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