Armstrong Air Conditioning A97DSMV, Installation Instructions Manual

Page: 21 / 68

507029-03 Page 21 of 68 Issue 1622
NOTE: Care must be taken to avoid recirculation of exhaust
back into intake pipe.
Details of Intake and Exhaust Piping Terminations for
Direct Vent Installations
NOTE: In Direct Vent installations, combustion air is taken
from outdoors and flue gases are discharged to outdoors.
Intake and exhaust pipes may be routed either horizontally
through and outside wall or vertically through the roof. In
attic or closet installations, vertical termination through
the roof is preferred. Figures 23 through 29 show typical
terminations.
1. Intake and exhaust terminations are not required to be
in the same paressure zone. You may exit the intake
on one side of the structure and the exhaust on another
side (Figure ). You may exit the exhaust out the roof
and the intake out the side of the structure (Figure ).
2. Intake and exhaust pipes should be placed as close
together as possible at termination end (refer to
illustrations). Maximum separation is 3” (76 mm) on roof
terminations and 6” (152 mm) on sidewall terminations.
3. On roof terminations, the intake piping should terminate
straight down using two 90° elbows (See Figure 21).
4. Exhaust piping must terminate straight out or up as
shown. A reducer is required on the exhaust piping
at the point where it exits the structure to improve the
velocity of exhaust away from the intake piping. See
Table 6.
Direct Vent Roof Termination Kit
Figure 21
Figure 22
Exiting Exhaust and Intake Vent
Figure 23
Exiting Exhaust and Intake Vent