User's Manual
23552-5-0608Page 22
To Use the Vent Graph (Figure 30)
1.  Determine  the height of the center  of the 
horizontal vent pipe. Using this dimension on 
the  Sidewall  Vent  Graph,  locate  the  point  it 
intersects with the slanted graph line.
2.  From the point of this intersection, draw a vertical 
line to the bottom of the graph.
3.  Select the indicated dimension, and position the 
unit in accordance with same.
EXAMPLE A:
If the vertical dimension from the floor of the unit 
is 12 feet, 4 inches the horizontal run to the outer 
wall flange must not exceed 12 feet, 3 inches.
EXAMPLE B:
If the vertical dimension from the floor of the unit 
is 6 feet, 9 inches, the horizontal run to the outer 
wall flange must not exceed 6 feet, 6 inches.
SPECIAL NOTE: For each 45 degree elbow 
installed  in  the  horizontal  run,  the  length  of  the 
horizontal run MUST be reduced by 18" (457 mm). 
This does  not apply  if the  45 degree  elbows are 
installed  on  the  vertical  part  of  the  vent  system. 
Reduce 3' for every 90° elbow.
Example: According  to  the  chart  the  maximum 
horizontal vent length is 20' and if two 45 degree 
elbows are required in the horizontal vent it must 
be reduced to 17'.
The maximum number  of 45  degree  elbows 
permitted per side  wall installation is two (2). 
These elbows can be installed in either the vertical 
or horizontal run.
  Acceptable vertical and horizontal vent run.
  Unacceptable vertical and horizontal vent run.
Note: When rear venting unit, adjust air shutter from 1/16" open 
up to between 1/8" and 3/16" for NAT gas.
Adjust air shutter from 1/4" open to between 5/16" and 3/8" for 
LP gas.
Figure 30
Venting Graph (Dimensions in Feet)
Note: When rear venting unit, adjust air shutter 
from 1/16" open up to between 1/8" and 3/16" 
for NAT gas.
Adjust  air  shutter  from  1/4"  open  to  between 
5/16" and to 3/8" for LP gas.
VERTICAL DIMENSION
FROM
THE
BOTT
OM
OF
THE
UNIT
TO
THE
CENTER
OF
THE
FLUE
OUTLET
WITH
VERTICAL
OR
HORIZONT
AL TERMINA
TION
CAPS
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
HORIZONTAL RUN
REAR EXIT - VERTICAL AND HORIZONTAL TERMINATION
(DIMENSIONS IN FEET)
REAR HORIZONTAL
VENT CONNECTION
B
A
DVD48FP(ONLY)
VENTING FIREPLACE - REAR










