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NOTES:
1. If an offset is necessary in the attic to avoid
obstructions, it is important to support the vent
pipe every
3’ (914 mm)
using wall straps to avoid
excessive stress on the elbows.
2.
Use 45
°
degree elbows instead of 90
°
degree
elbows when ever possible. The 45
°
degree elbow
offers less restriction to the flow of flue gases and
intake air.
Horizontal Termination:
1. A minimum of 12" vertical rise before
an elbow is required when horizontally
terminating with an approved venting cap.
2.
Horizontal pipes must not be level. For
every 12” (305 mm) of horizontal travel there
should be at least ¼” (6.4 mm) of vertical
rise. Never allow the vent to run downward,
as this could cause high temperatures or
even present the possibility of a fire.
3.
The exterior of the horizontal vent termination
must not be blocked or obstructed.
4.
If the vent termination is not being attached
to wood, the four wood screws provided should
be replaced with material appropriate fasteners.
5.
For buildings with vinyl siding, a vinyl standoff
should be installed between the vent cap and
Wall Framing
Horizontal
Termination
Wall Thimble
Fire Stop
Exhaust Pipe
Combustion Air
Outer Pipe
Elbow
the exterior wall. Attach the vinyl siding standoff
to the horizontal termination. The termination
attaches to the flat portion of the standoff which
provides an air space between the wall and the
vent termination. The air gap prevents excessive
heat from possibly melting the vinyl siding.
6.
Horizontal pipes must be supported every
3’
(914 mm)
. Plumber’s “all round” strap will suffice.
7.
Clearances to combustibles must be maintained
when running horizontal pipe.
1” (25 mm)
sides,
1” (25 mm)
bottom,
3” (76 mm)
top, and
3” (76
mm)
above elbows outside the immidiate chase.
8.
Set the fireplace in the desired location.
Check to determine if wall studs will be in the way
when the venting system is attached. If this is the
case, the location of the fireplace may have to be
adjusted or the venting may have to be offset.
9.
Many
direct vent pipe sections are
designed with special twist-lock connections.
Dry fit the desired combination of pipe
and elbows to the appliance adaptor.
10.
With the pipe in the correct position and attached
to the fireplace, mark the wall for a hole as directed
by specified wall thimble dimensions. Cut and frame
the hole in the exterior wall where the vent will be
terminated. If the wall being penetrated is made of a
non-combustible material (i.e. masonry or concrete)
a minimum
7 1/2” (191mm)
hole is acceptable.
Framing and Installation
Venting
