Empire Comfort Systems CIDV-30-7 - Manual (Page 11)

Page 11 R-5086
Venting Graph (Dimensions in Feet) (Figure 16)
1. Determine the height of the center of the termination. Using this
dimension on the Venting Graph, locate the point it intersects with the
slanted graph line, or the right edge of the graph.
2. From the point of this intersection, draw a vertical line to the bottom
of the graph.
3. Adjust the indicated maximum dimension for additional elbows if
necessary.
4. Position the unit so that maximum horizontal run is not exceeded.
Venting Must Be Within Shaded Area
Figure 16
Venting Requirements (Figure 17)
Minimum vertical rise from appliance outlet = 24 inches (610mm)
Attention: All vent runs must have a minimum VERTICAL rise of
two feet. If the vent run is directly behind the appliance, you must
attach Simpson Dura-Vent 36" snorkel, part number SD-981 on the
exterior of the building.
Maximum vertical rise from appliance outlet = 25 feet (7.62m), the
restrictor plate may be used above 10 feet.
Maximum horizontal run from appliance outlet = 12 feet (3.66m)
Maximum vertical rise and horizontal run is a combined total of 25 feet
(7.62m)
Maximum elbows = (2) 90
°
, for the second elbow subtract 5 feet from a
horizontal run.
To Use the Vent Graph
EXAMPLE A:
If the vertical rise from the appliance outlet is 21 feet, the horizontal run
to the outer wall flange of the vent termination must not exceed 4 feet with
(1) 90
°
elbow.
EXAMPLE B:
If the vertical rise from the appliance outlet is 14 feet, the horizontal run
to the outer wall flange of the vent tremination must not exceed 11 feet
with (1) 90
°
elbow.
SPECIAL NOTE: For each 45 degree elbow installed in the horizontal
run, the length of the horizontal run MUST be reduced by 18 inches
(45cm). This does not apply if the 45 degree elbows are installed on the
vertical rise of the vent system.
Example: According to the chart the maximum horizontal run is 12 feet
and if two 45 degree elbows are required in the horizontal run it must be
reduced to 9 feet.
The maximum number of 45 degree elbows permitted per side wall
installation is two. These elbows can be installed in either the vertical rise
or horizontal run.
Figure 17