Installation Instructions

Do not terminate the vent system into an attic or other
enclosed area.
Do not use a 4” (10.2 cm) laundry-type wall cap.
Rigid metal vent is recommended.
Plastic or metal foil vent is not recommended.
The length of vent system and number of elbows
should be kept to a minimum to provide efcient
performance.
For the most efcient and quiet operation:
Use no more than three 90° elbows.
Make sure there is a minimum of 24” (61 cm) of straight
vent between the elbows if more than 1 elbow is used.
Do not install 2 elbows together.
Use clamps or duct tape to seal all joints in the
vent system.
The vent system at exit must have a cold air damper.
Use caulking to seal exterior wall or roof opening
around the cap.
Best performances are reached with straight piping,
without elbows and using smooth pipe.
Cold Weather Installations
An additional back draft damper should be installed to
minimize backward cold air ow and a thermal break
should be installed to minimize conduction of outside tem-
peratures 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
specied CFM of air movement. The specied CFM varies
from locale to locale. Consult your HVAC professional for
specic requirements in your area.
Venting Methods
Vent system can terminate either through the roof or wall.
Use 3¼” x 10” (8.3 x 25.4 cm) rectangular with a maximum
vent length of 35 ft (10.7 m)
for vent system.
NOTE
Flexible vent is not recommended. Flexible vent
creates both back pressure and air turbulence
that greatly reduce performance.
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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.
Roof Venting Wall Venting
VENTING REQUIREMENTS
Use metal vent only.
These directions are for rectangular vent installation only.
If you choose to use round rigid metal venting the minimum
diameter to use is """"""""''''"'"""" .??????
8”
3¼” x 10” (8.3 cm x 25.4 cm) rectangular Vent System
Vent Piece
3¼” x 10” (8.3 cm x 25.4 cm) 5.0 ft
90° elbow (1.5 m)
3¼” x 10” (8.3 cm x 25.4 cm) 12.0 ft
flat elbow (3.7 m)
3¼” x 10” (8.3 cm x 25.4 cm) 0.0 ft
wall cap (0.0 m)
Example Vent System
Maximum Recommended Length = 35 ft (10.7 m)
1 - 90° elbow = 5.0 ft (1.5 m)
8 ft (2.4 m) straight = 8.0 ft (2.4 m)
1 - wall cap = 0.0 ft (0.0 m)
Length of 3¼” x 10” = 13.0 ft (3.9 m)
(8.3 cm x 25.4 cm) system
2 ft
(0.6 m)
3¼” x 10”
(8.3 x 25.4 cm)
elbow
6 ft (1.8 m)
Wall Cap
EN-7