Installation Instructions

5
Venting Requirements
■ Vent system must terminate to the outdoors.
■ Do not terminate the vent system in an attic or other enclosed
area.
■ Do not use 4" (10.2 cm) laundry-type wall caps.
■ Use round, metal venting only. Rigid metal venting is
recommended. Plastic or metal foil venting is not
recommended.
■ The length of the vent system and the number of elbows
should be kept to a minimum to provide efficient
performance.
For the Most Efficient and Quiet Operation:
■ Use no more than three 90° elbows.
■ Make sure there is a minimum of 24" (61.0 cm) of straight
vent between the elbows if more than 1 elbow is used.
■ Do not install 2 elbows together.
■ Use clamps and metal duct tape to seal all joints in the vent
system.
■ The vent system must have a damper.
■ Use weatherproof caulking compound to seal the exterior
wall or roof opening around the cap.
■ The size of all venting should be uniform.
Cold Weather Installations
An additional back draft damper should be installed to minimize
backward cold air flow. A thermal break should be installed to
minimize conduction of outside temperatures as part of the vent
system. The damper should be on the cold air side of the thermal
break.
The break should be as close as possible to where the vent
system enters the heated portion of the house.
Makeup Air
Local building codes may require the use of makeup air systems
when using ventilation systems greater than specified CFM of air
movement. The specified CFM varies from locale to locale.
Consult your HVAC professional for specific requirements in your
area.
Typical In-Line Smart Kit Installations
A 6" (15.2 cm) round vent system is needed for installations (not
included).
The In-Line Smart Kit inlet and outlet openings are 6" (15.2 cm)
round. The exhaust (outlet) opening on the range hood must also
be 6" (15.2 cm) round.
NOTE: Flexible vent is not recommended. Flexible vents create
back pressure and air turbulence that can greatly reduce In-Line
Smart Kit performance.
The vent system may terminate either through the roof or wall.
NOTE: Plywood may be used as a mounting base to span open
areas between ceiling joists and rafters. If used, be sure to use
plywood capable of supporting 25 Ib (11.3 kg).
Calculating Vent System Length
To calculate the length of the system you need, add the
equivalent feet (meters) for each vent piece used in the system.
The maximum recommended equivalent vent length is 35 ft
(10.7 m).
Example Vent System
The following example falls within the maximum recommended
vent length of 35 ft (10.7 m).
A. Mounted on top of ceiling joists (vertical duct)
B. Mounted to cross-members tied to trusses
(horizontal duct)
Vent Piece 6" (15.2 cm) Round
45° elbow 2.5 ft
(0.8 m)
90° elbow 5.0 ft
(1.5 m)
1 - 90° elbow = 5.0 ft (1.5 m)
1 - wall cap = 0.0 ft (0.0 m)
8 ft (2.4 m) straight = 8.0 ft (2.4 m)
Length of system = 13.0 ft (3.9 m)
A
B
90 elbow
6 ft (1.8 m)
2 ft
(0.6 m)
Wall cap