Heat & Glo • EVEREST-B • 2367-900 Rev. G • 6/18
23
H
1
V
1
To replace the first starter elbow with two 45º elbows,
refer to Figure 7.3. All other 90º elbows can be replaced
with two 45º elbows.
General Rules:
• SUBTRACT 3 ft. from the total H measurement for each
90º elbow installed horizontally.
• SUBTRACT 1-1/2 ft. from the total H measurement for
each 45º elbow installed horizontally.
• A maximum of three 90º elbows (or six 45º elbows) may
be used in any vent configuration. Some elbows may be
installed horizontally. See Figure 7.9.
• Elbows may be placed back to back anywhere in the
system as long as the first 90º elbow is a starter elbow
except as shown in Figure 7.4.
• When penetrating a combustible wall, a wall shield
firestop must be installed.
• When penetrating a combustible ceiling, a ceiling firestop
must be installed.
• Horizontal runs of vent do not require vertical rise;
horizontal runs may be level.
• Horizontal termination cap should have a 1/4 inch
downward slant to allow any moisture in cap to be
released.
E. Vent Diagrams
V
1
Minimum
H
1
Maximum
Elbow only
2 ft
610 mm
1 ft.
305 mm
9 ft.
2.7 m
2 ft.
610 mm
14 ft.
4.3 m
4 ft.
1.2 m
19 ft.
5.8 m
V
1
+ H
1
= 40 ft. (12.2 m) Maximum
H
1
= 20 ft. (6.1 m) Maximum
Fire Risk. Explosion Risk.
Do NOT pack insulation or other combustibles
between ceiling firestops.
• ALWAYS maintain specified clearances around
venting and firestop systems.
• Install wall shield and ceiling firestops as speci
-
fied.
Failure to keep insulation or other material away
from vent pipe may cause fire.
Fire Risk. Explosion Risk.
Do NOT pack insulation or other combustibles
between ceiling firestops.
• ALWAYS maintain specified clearances around
venting and firestop systems.
• Install wall shield and ceiling firestops as speci
-
fied.
Failure to keep insulation or other material away
from vent pipe may cause fire.
Figure 7.3 Venting with One 90° Elbow
Top Vent - Horizontal Termination
One Elbow
WARNING
NOTE:
For corner installations: A 6 inch (152 mm) section of
straight pipe may need to be attached to the fireplace before a
90º elbow, to allow the vent pipe to clear the top standoffs.
