6
HORIZONTAL INSTALLATION REQUIREMENTS
• When venting through a sidewall, terminate the system not less than 12”
(.3m) above the ground and above the snow line in geographical areas
where snow accumulates. The termination area must be kept clear of
snow and ice at all times. See
Figure 1.
• Terminate the system at least 7’ (2.1m) above a public walkway or
driveway, no less than 6’ (1.8m) from the combustion air intake of any
appliance or 3’ (.9m) from any other building opening, gas utility meter,
service regulator or the like. Less distance is permitted if specified in the
appliance’s installation instructions. It also shall terminate at least 3’ (.9M)
above any forced air inlet within 10’ (3.1m) and shall terminate at least 4’
(1.2m) below, 4’ horizontally from, or 1’ (.3m) above any door, window, or
gravity air inlet into any building as provided in the National Fuel Gas Code
ANSI Z223.1 and NFPA 54. See
Figure 1
. Proper judgment may require
greater distances depending on the side of the equipment installed or
to allow for snow drifting or falling from falling from overhead roofs or
trees. The termination should be far enough away from trees, shrubs,
or decorative items to prevent damage.
• The total horizontal vent length from the appliance flue collar to the outside
termination shall be in accordance with the appliance manufacturer’s
instructions.
MVS : Maximum Vertical Spacing between Guides/Supports
MHS: Maximum Horizontal Spacing between Guides/Supports
MDE: Maximum Distance between Elbows
H: Maximum Freestanding Height above the Roof
S: Maximum Suspended Length
SUPPORT AND GUIDE SPACING FOR MODEL DS & DSLS
Inside
diameter
MVS
MHS
MDE
H
S
Interior
Exterior
3”
10
8
12
12
10
50
4”
10
8
12
12
10
100
5”
10
8
12
12
10
100
6”
10
8
12
12
10
100
7”
10
8
12
12
10
100
8”
10
8
12
12
10
100
9”
10
8
12
12
10
100
10”
10
8
12
12
10
100
12”
10
8
12
12
10
100
14”
10
8
12
12
10
100
16”
10
8
12
12
10
100
18”
10
8
12
12
10
100
20”
10
8
12
12
10
100
22”
10
8
12
12
10
100
24”
10
8
12
12
10
100
26”
10
8
12
12
12
100
28”
10
8
12
12
12
100
30”
10
8
12
12
12
100
32”
10
8
12
12
12
100
34”
10
8
12
12
12
100
36”
10
8
12
12
12
100
Table 7: Support and Guide Spacing for Model DS & DSLS. Dimensions are in feet
SUPPORT AND GUIDE SPACING FOR MODEL DSD & DSID & DSLD
Inside
diameter
MVS
MHS
MDE
H
S
Interior
Exterior
3”
10
8
12
12
10
50
4”
10
8
12
12
10
50
5”
10
8
12
12
10
50
6”
10
8
12
12
10
50
7”
10
8
12
12
10
50
8”
10
8
12
12
10
50
9”
10
8
12
12
10
50
10”
10
8
12
12
10
50
12”
10
8
12
12
10
50
14”
10
8
12
12
10
50
16”
10
8
12
12
10
50
18”
10
8
12
12
10
50
20”
10
8
12
12
10
50
22”
10
8
12
12
10
50
24”
10
8
12
12
10
50
26”
10
8
12
12
12
50
28”
10
8
12
12
12
50
30”
10
8
12
12
12
50
32”
10
8
12
12
12
50
34”
10
8
12
12
12
50
36”
10
8
12
12
12
50
Table 8: Support and Guide Spacing for Model DSD, DSID & DSLD. Dimensions are in feet
7 ft above
public
walkways
and drives
1 ft. above doors and windows
4 ft below any
window or fresh air
inlet
1 ft. above ground or
snow line
Sidewalk
Figure 1 - Horizontal Termination Requirements
4 ft. horizontally from door
and windows
