Empire Comfort Systems DVCP36BP0N-2 Installation Instructions And Owner's Manual page 31

If two vertical terminations are run near each other, they may be
placed a minimum of 12 inches between them if they are at the
same height. See Figure 61. If two vent terminations are not at
the same height, they must be positioned at least 24 inches apart
to minimize draft issues between them.
35919-4-1015
VERTICAL TERMINATION (continued)
Figure 60
12"
MINIMUM
Figure 61
Vertical Through the Roof Applications
Your Gas Fireplace has been approved for:
a) Vertical installations up to 40 feet in height.
b) Two sets of 45 degree elbow offsets within these vertical
installations. From 0 to a maximum of 8 feet a vent pipe can be
used between elbows.
c) Wall straps must be used to support offset pipe every 4-ft.
This application will require that you first determine the roof pitch
and use the appropriate venting components.
OFFSET CHART
OFFSET
ELBOW CHIMNEY
DEGREES SECTION
45
45
45
45 12
45 24
45 36
45 36
45 48
RISE
OFFSET RISE
Dimensions in inches
0 4-7/8 13-3/8
6 8 16-1/2
9 10-1/8 18-5/8
12-1/4 20-3/4
20-5/8 29-1/8
29 37-1/2
29 37-1/2
37-3/8 45-7/8
Figure 62
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