Lennox G61MPV Service Manual page 64

G61MP DIRECT VENT APPLICATION
USING EXISTING CHIMNEY
8" − 12"
(203mm − 305mm)
Minimum 12" (305MM)
INTAKE PIPE
INSULATION (optional)
above chimney top
plate or average snow
METAL TOP
accumulation
INSULATE
TO FORM
SEAL
*SIZE TERMINATION
PIPE PER TABLE 38.
NOTE − Do not discharge exhaust gases directly into any chimney or vent stack. If ver-
tical 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 illus-
trated. In any exterior portion of chimney, the exhaust vent must be insulated.
FIGURE 42
Details of Exhaust Piping Terminations for Non-Direct
Vent Applications
Exhaust pipes 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 pre-
ferred. Figures 43 through 46 show typical terminations.
1. Exhaust piping must terminate straight out or up as
shown. The termination pipe must be sized as listed in
table 38.The specified pipe size ensures proper ve-
locity required to move the exhaust gases away from
the building.
2. On field supplied terminations for side wall exit, ex-
haust piping may extend a maximum of 12 inches
(305mm) for 2" PVC and 20 inches (508mm) for 3"
(76mm) PVC beyond the outside wall. See figure 44.
STRAIGHT−CUT OR
ANGLE−CUT IN DIRECTION
OF ROOF SLOPE *
3" − 8"
EXHAUST VENT
(76mm−
1/2" (13mm)
203mm)
WEATHERPROOF
INSULATION
SHOULDER OF FITTINGS
PROVIDE SUPPORT
OF PIPE ON TOP PLATE
SHEET
ALTERNATE
INTAKE PIPE
PLATE
3" − 8"
(76mm−
203mm)
EXTERIOR
PORTION OF
CHIMNEY
12" (305mm)
ABOVE AVE.
SNOW
ACCUMULATION
3" (76mm) OR
2" (51mm) PVC
PROVIDE SUPPORT
FOR EXHAUST LINES
NON−DIRECT VENT ROOF TERMINATION KIT
1/2" (13mm) ARMAFLEX
INSULATION IN
UNCONDITIONED SPACE
FIELD−PROVIDED
REDUCER MAY
BE REQUIRED TO
ADAPT LARGER
VENT PIPE SIZE
TO TERMINATION
SIZE TERMINATION
PIPE PER TABLE 38.
NON−DIRECT VENT FIELD SUPPLIED WALL TERMINATION OR
(15F74) WALL TERMINATION KIT
3. If exhaust piping must be run up a side wall to position
above snow accumulation or other obstructions, pip-
ing must be supported every 24 inches (610mm) as
shown in figure 45. When exhaust piping must be run
up an outside wall, any reduction in exhaust pipe size
must be done after the final elbow.
Page 64
SIZE TERMINATION
PIPE PER TABLE
38.
1/2" (13mm) FOAM
INSULATION
UNCONDITIONED
ATTIC SPACE
(15F75 or 44J41)
FIGURE 43
12" (305mm) MAX. for 2" (51mm)
20" (508mm) MAX. for 3" (76mm)
PVC REDUCER
12" MIN.
(305mm)
Above Grade or
average snow
accumulation
FIGURE 44
1/2" (13mm)
ARMAFLEX
INSULATION