507052-05
Page 30 of 54
Issue 1922
Details of Exhaust Piping Terminations for Non-
Direct Vent Applications
Exhaust pipe may be routed either horizontally through
an outside wall or vertically through the roof. In attic or
closet installations, vertical termination through the roof
is preferred. Figure 39 through Figure 42 show typical
terminations.
1. Exhaust piping must terminate straight out or up as
shown. The termination pipe must be sized as listed
in Table 9. The specified pipe size ensures proper
velocity required to move the exhaust gases away
from the building.
2. On field supplied terminations for side wall exit,
exhaust piping may extend a maximum of 12 inches
(305 mm) for 2” PVC and 20” (508 mm) for 3” (76 mm)
PVC beyond the outside wall. See Figure 40.
3. If exhaust piping must be run up a sidewall to position
above snow accumulation or other obstructions, piping
must be supported every 24” (610 mm) as shown in
Figure 41. When exhaust piping must be run up an
outside wall, any reduction in exhaust pipe size must
be done after the final elbow.
Figure 39.
Non-Direct Vent Roof Termination Kit
(15F75 or 44J41)
UNCONDITIONED
ATTIC SPACE
3” (76MM) OR
2” (51MM) PVC
PROVIDE SUPPORT
FOR EXHAUST LINES
12” (305MM)
ABOVE AVE.
SNOW
ACCUMULATION
SIZE PER EXHAUST PIPE
TERMINATION SIZE
REDUCTION TABLE
Figure 40.
Non-Direct Vent Field Supplied Wall
Termination
SIZE TERMINATION
PER EXHAUST PIPE
TERMINATION SIZE
REDUCTION TABLE
Figure 41.
Non-Direct Vent Field Supplied Wall
Termination - Extended
SIZE TERMINATION
PER EXHAUST PIPE
TERMINATION SIZE
REDUCTION TABLE
* Use wall support every 24” (610 mm). Use two supports of extension is greater than 24”
(610 mm) but less than 48” (1219 mm).
STRAIGHT-CUT OR
ANGLE-CUT IN DIRECTION
OF ROOF SLOPE
SHOULDER OF FITTINGS
PROVIDE SUPPORT
OF PIPE ON TOP PLATE
EXTERIOR
PORTION OF
CHIMNEY
INSULATE
TO FORM
SEAL
SHEET
METAL TOP
PLATE
Minimum 12” (305MM)
above chimney top
plate or average snow
accumulation
* SIZE TERMINATION PIPE
PER EXHAUST PIPE TERMINATION
SIZE REDUCTION TABLE
NOTE
: Do not discharge exhaust gases directly into any
chimney or vent stack. If vertical discharge through an existing
unused chimney or stack is required, insert piping inside
chimney until the pipe open end is above top of chimney and
terminate as illustrated. In any exterior portion of chimney, the
exhaust vent must be insulated.
Figure 42.
Non-Direct Vent Application Using Existing
Chimney
