Heatilator • CD4236IFTR, CD4236IFTLR, CD4842IFTR, CD4842IFTLR Installation Manual • 2511-980 Rev. M
• 8/21
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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. For example, see Figure 4.19.
• Elbows may be placed back to back anywhere in the
system.
•
Any 90º elbow may be replaced with two back to back
45º elbows.
• 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. See Figure 4.9.
F. Vent Diagrams
Figure 4.9
1/4 in. max.
(6 mm)