14
Heatilator • GNTC50 • 4002-095 Rev H • 06/07
Fire Risk
Explosion Risk
Do NOT pack insulation or other combustibles between
fi
restops.
• ALWAYS maintain speci
fi
ed clearances around venting and
fi
restop systems.
• Install
fi
restops as speci
fi
ed.
Failure to keep insulation or other material away from vent pipe may cause
fi
re.
WARNING
D. Vent Diagrams
To replace the
fi
rst starter elbow with two 45° elbows, refer to Figure 5.4. All other 90° elbows can be replaced with two 45°
elbows.
General Rules:
•
SUBTRACT 3 ft/.91 m from the total H measurement for each 90° elbow installed horizontally.
SUBTRACT 1-1/2 ft/.46 m from the total H measurement for each 45° elbow installed horizontally.
•
A maximum of three 90° elbows (or six 45° elbows) may be used in any vent con
fi
guration. Some elbows may be installed
horizontally. See Figure 5.6.
•
Elbows may be placed back to back anywhere in the system except as shown in Figure 5.4.
• When penetrating a combustible wall, a wall shield
fi
restop must be installed.
• When penetrating a combustible ceiling, a ceiling
fi
restop must be installed.
• Horizontal runs of vent do not require vertical rise; horizontal runs may be level.
H
1
V
1
Figure 5.3 Top Vent-Horizontal Termination-One Elbow
Top Vent—Horizontal Termination—One Elbow
V
1
min.
V
1
max.
H
1
max.
0*
-
24 in./635 mm
4 in./102 mm
-
4 ft/1.22 m
6 in./152 mm
-
6 ft/1.83 m
12 in./305 mm
-
11 ft/3.35 m
18 in./457 mm
-
18 ft/5.49 m
24 in./610 mm
-
25 ft/7.62 m
-
25 ft/7.62 m
25 ft/7.62 m
You may install the elbow directly on top of
the appliance.
Table 5.1
