Lennox EL297DFV Series Unit Information page 55

7 - I f intake and exhaust piping must be run up a side
wall to position above snow accumulation or other
obstructions, piping must be supported. At least
one bracket must be used within 6" from the top of
the elbow and then every 24" (610mm) as shown
in FIGURE 37, to prevent any movement in any
direction. When exhaust and intake piping must be
run up an outside
NOTE − FIELD−PROVIDED
REDUCER MAY BE
REQUIRED TO ADAPT
LARGER VENT PIPE SIZE
TO TERMINATION
C1
* WALL
SUPPORT
E
C1
ALTERNATE TERMINATIONS (TEE & FORTY−FIVE DEGREE ELBOWS ONLY)
B D
C
2
A
D
E
B
C
2
A
FIELD FABRICATED WALL TERMINATION
D
B
Intake
C2
Elbow
A
STRAIGHT
APPPLICATION
D
E
B
A
C2
EXTENDED
APPLICATION
B
D
1
C
Intake
Elbow A
D
E
B
1
C
2
12"
A
1
The exhaust termination tee should be connected to the 2" or 3" PVC flue pipe as shown in the illustration. In
horizontal tee applications there must be be a minimum of 3 ft away from covered patios or any living ares and
cannot be within 3 ft of a window. Do not use an accelerator in applications that include an exhaust termination
tee. The accelerator is not required.
2
As required. Flue gas may be acidic and may adversely affect some building materials. If a side wall vent
termination is used and flue gases will impinge on the building materials, a corrosion−resistant shield
(24 inches square) should be used to protect the wall surface. If optional tee is used, the protective shield
is recommended. The shield should be constructed using wood, sheet metal or other suitable material.
All seams, joints, cracks, etc. in affected area, should be sealed using an appropriate sealant.
3
Exhaust pipe 45° elbow can be rotated to the side away from the combustion air inlet to direct exhaust
away from adjacent property. The exhaust must never be directed toward the combustion air inlet.
wall, the exhaust piping must be terminated with pipe
sized per TABLE 24.The intake piping may be equipped
with a 90° elbow turndown. Using turndown will add 5
feet (1.5m) 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 shown in FIGURE 40.
A− Minimum clearance
above grade or average
snow accumulation
D
B− Maximum horizontal
separation between
intake and exhaust
C1 -Minimum from end of
B
exhaust to inlet of intake
C2 -Minimum from end of
A
exhaust to inlet of intake
D− Maximum exhaust
pipe length
E− Maximum wall support
D
distance from top of each
pipe (intake/exhaust)
See maximum allowable venting tables for venting
B
lengths with this arrangement.
* Use wall support every 24" (610 mm). Use two
wall supports if extension is greater than
A
24" (610 mm) but less than 48" (1219 mm).
NOTE − One wall support must be within 6" (152 mm)
from top of each pipe (intake and exhaust) to prevent
movement in any direction.
A - Clearance above
Grade or average snow
Exhaust
accumulation
B - Horizontal separation
between intake and exhaust
3
C - Minimum from end of
exhaust to inlet of intake
D - Exhaust pipe length
E - Wall support distance from
top of each pipe
(intake/exhaust)
1
D
E
B
12"
C
A
FIGURE 37
Page 55
2" (51mm) 3" (76mm)
Vent Pipe Vent Pipe
12" (305 mm) 12" (305 mm)
6" (152 mm) 6" (152 mm)
8" (203 mm) 8" (203 mm)
6" (152 mm) 6" (152 mm)
12" (305 mm) 20" (508 mm)
6" (152 mm) 6" (152 mm)
2" (51mm) 3" (76mm)
Vent Pipe Vent Pipe
12" (305 mm) Min 12" (305 mm) Min
6" (152mm)min
6" (152mm)min
24" (610mm )Max
24" (610mm )Max
9" (227mm) 9" (227mm)
12" (305mm)min 12" (305mm)min
16" (405mm )Max 16" (405mm )Max
6" (152mm) Max 6" (152mm) Max
Front View of
Intake and Exhaust
Intake
Exhaust