507266-04B
Page 30 of 56
Issue 1904
7. If intake and exhaust piping must be run up a side
wall to position above snow accumulation or other
obstructions, piping must be supported every 24”
(610 mm) as shown in Figure 44. Exhaust and
intake piping that is run up a wall is considered to
be in an unconditioned space, so piping should be
sized according to Table 6. The intake piping may be
equipped with a 90° elbow turndown. Using turndown
will add 5 feet (1.5 m) to the equivalent length of the
pipe.
8. A multiple furnace installation may use a group of up to
four terminations assembled together horizontally, as
Figure 39. Direct Vent Concentric Rooftop
Termination
71M80, 69M29 or 60L46 (US)
41W92 or 41W93 (Canada)
Figure 40.
Flush-Mount Side Wall Termination
51W11
Figure 41. Direct Vent Concentric Wall Termination
71M80, 69M29 OR 60L46 (US)
41W92 or 41W93 (Canada)
Figure 42. Optional Vent Termination for Multiple Unit
Installation of Direct Vent Wall Termination
Figure 43. Direct Vent Application Using Existing
Chimney
3” - 8”
(76MM-
203MM)
STRAIGHT-CUT OR
ANGLE-CUT IN DIRECTION
OF ROOF SLOPE
SHOULDER OF FITTINGS
PROVIDE SUPPORT
OF PIPE ON TOP PLATE
ALTERNATE
INTAKE PIPE
INTAKE PIPE
INSULATION (optional)
EXTERIOR
PORTION OF
CHIMNEY
INSULATE
TO FORM
SEAL
SHEET
METAL TOP
PLATE
Minimum 12” (305MM)
above chimney top
plate or average snow
accumulation
8” - 12”
(203MM - 305MM)
3”-8”
(76MM-203MM)
* 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 terminates as
illustrated. In any exterior portion of chimney, the exhaust vent
must be insulated.