GCSS96 Installation Manual

17
90º OR 45°
ELBOW
12" MIN. TO GRADE OR
HIGHEST ANTICIPATED
SNOW LEVEL
6” MAX
10”- 24”
4” MIN
Standard Horizontal Terminations (Dual Pipe)
Figure 15
DIRECT VENT (DUAL PIPE) PIPING
Direct vent installations require both a combustion air intake
and a vent/flue pipe. The pipes may be run horizontally and exit
through the side of the building or run vertically and exit through
the roof of the building. The pipes may be run through an exist-
ing unused chimney; however, they must extend a minimum of
12 inches above the top of the chimney. The space between the
pipes and the chimney must be closed with a weather tight,
corrosion resistant flashing. Both the combustion air intake and
a vent/flue pipe terminations must be in the same atmospheric
pressure zone. Refer to Vent/Flue and Combustion Air Pipe -
Termination Locations or Concentric Vent Termination for spe-
cific details on termination construction. For details concerning
connection of pipes to the furnace, refer to the Vent/Flue Pipe
and Combustion Pipe - Standard Furnace Connections or Alter-
nate Furnace Connections.
90°
ELBOWS
12" MIN. ABOVE
HIGHEST ANTICIPATED
SNOW LEVEL
3” - 24”
Alternate Horizontal Vent Termination (Dual Pipe)
Figure 16
VENT/FLUE & COMBUSTION AIR PIPE LENGTHS & DIAMETERS
Refer to the following table for applicable length, elbows, and
pipe diameter for construction of the vent/flue and combustion
air intake pipe systems of a direct vent (dual pipe) installation.
The number of elbows tabulated represents the number of el-
bows and/or tees in each (Vent/Flue & Combustion Air Intake)
pipe. Elbows and/or tees used in the terminations must be in-
cluded when determining the number of elbows in the piping
systems.
If the combustion air intake pipe is to be installed above a fin-
ished ceiling or other area where dripping of condensate will be
objectionable, insulation of the combustion air pipe may be re-
quired.
90°
ELBOWS
12" MIN. ABOVE
HIGHEST ANTICIPATED
SNOW LEVEL
3”-24” BETWEEN PIPES
Combustion Air Intake may also be snorkeled
to obtain 12” min ground clearance.
Alternate Vent Termination Above Anticipated Snow Level
(Dual Pipe)
Figure 17