Empire Comfort Systems DVX42DP31P-3 Installation Instructions And Owner's Manual page 19

VENTING FIREPLACE - TOP (continued)
Below Grade Installation
When it is not possible to meet the required vent terminal clearances
of 12" (305mm) above grade level, a snorkel kit is recommended.
It allows installation depth down to 7" (178 mm) below grade level.
The 7" (178 mm) is measured from the center of the horizontal vent
pipe as it penetrates through the wall.
Ensure the sidewall venting clearances are observed. If venting
system is installed below ground, we recommend a window
well with adequate and proper drainage to be installed around
the termination area.
TYPICAL BASEMENT INSTALLATION
Examples of possible venting systems using one 90° elbow. Eight
feet is listed as minimum vertical vent run with 20 feet of maximum
horizontal vent run. Vertical dimensions are based on centerline to
centerline of pipe. Horizontal dimensions are based on centerline
of pipe to end of termination.
31453-6-0914
Figure 23
Examples of possible venting systems using two 90° elbows.
V is listed as minimum vertical dimensions and H1 + H2 is listed
as total of maximum horizontal dimensions. The maximum vertical
and horizontal distances for two 90° elbows as shown in Figure
25 is 22 feet.
Attention: Refer to Figure 20 for additional venting requirements.
Figure 24
Figure 25
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