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Outdoor Lifestyles by Hearth & Home Technologies • Fortress - ODFORTG-36 Installation Manual • 4602-901 Rev B • 8/17
B. Installation Planning
There are two basic types of direct-vent installation:
•
Horizontal Termination
•
Vertical Termination
It is important to select the proper length of vent pipe for
the type of termination you choose. It is also important to
note the wall thickness.
For Horizontal Termination
Select the amount of vertical rise desired. All horizontal run
of venting must have 1/4" rise for every 12" of run towards
the termination below 7
1
⁄
2
" of vertical rise from floor of fire
-
place. With 7
1
⁄
2
feet or more of vertical rise from the floor
of the fireplace, the horizontal run may be level. NEVER
run vent piping down.
You may use up to three 90° elbows in this vent configura
-
tion. Refer to Vertical/Horizontal Termination Configurations
on Page 20.
For Vertical Termination
Measure the distance from the fireplace floor to the ceil
-
ing. Add the ceiling thickness, the vertical rise in an attic
or second story, and allow for sufficient vent height above
the roof line.
NOTE: You may use two 45° elbows in place of a 90°
elbow. You must follow rise to run ratios when using
45° elbows. The appliance is approved for use with
three 90° elbows maximum or a combination of 90°
and 45° elbows up to a maximum of 270°.
NOTICE:
When installing in a chase, you should
insulate the chase as you would the outside walls
of your home. This is especially important in
cold climates. Insulation should be considered a
combustible material. Maintain proper clearances
to all combustible materials.
NOTICE:
Treatment of firestops and construction of
the chase may vary from building type to building
type. These instructions are not substitutes for the
requirements of local building codes. You must follow
all local building codes.
Never run the vent pipe down. This may cause
excessive temperatures which could cause
a fire.
For two-story applications, firestops are required at each
floor level. If an offset is needed in the attic, additional pipe
and elbows will be required.
You may use a chase with a vent termination with exposed
pipe on the exterior of the house. See
Installing Vent
System in a Chase
below. If pipe is enclosed in chase, it
is not exposed.
It is very important that the venting system maintain its bal-
ance between the combustion air intake and the flue gas
exhaust. Certain limitations apply to vent configurations
and must be strictly followed.
C. Installation Instructions
Installing a Vent System in an Outside
Chase
A chase is a vertical boxlike structure built to enclose
venting that runs along the outside of a building. A chase
is required for such venting.
WARNING
Always maintain minimum clearances around
vent systems. The minimum clearances to
combustibles for horizontal vent pipe are 3”
at the top* and 1” at the sides and bottom
of the vent system until the pipe penetrates
the nearest vertical wall (1” required). A 1”
minimum clearance all around the pipe must be
maintained at outside wall and on vertical runs.
Do not pack the open air spaces with insulation
or other materials. This could cause high
temperatures and may present a fire hazard.
*Unless the vertical run is 7
1
⁄
2
feet or higher
from floor of fireplace, the clearance for the
horizontal run is 1” on all sides.
WARNING
