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Majestic • MERID36IN, MERID36IL, MERID42IN, MERID42IL Installation Manual • 2517-980 Rev. C • 3/18
E. Measuring Standards
Vertical and horizontal measurements listed in the vent
diagrams were made using the following standards:
• Pipe measurements are shown using the effective length
of pipe. See Section 12.A (Figure 12.1 for DVP, Figure
12.8 for SLP) for information on effective length of pipe
components.
• Horizontal terminations are measured to the outside
mounting surface (flange of termination cap) (see Figure
4.6).
• Vertical terminations are measured to top of last section
of pipe. See Figure 4.7.
• Horizontal pipe installed level with no rise.
MEASURE TO SHADED SURFACE
(OUTSIDE MOUNTING SURFACE)
Figure 4.6 Measure to Outside Mounting Surface
Figure 4.7 Measure to Top of Last Section of Pipe
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 4.24.
• 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 4.8.
F. Vent Diagrams
Figure 4.8
W
A
LL
1/4 in. max.
(6 mm)