Modine Manufacturing DBS Installation And Service Manual page 9

INSTALLATION - VENTING
Section B - Vertical 2-Pipe Vent System
Installation
B1. This section applies to vertically vented 2-pipe (one
combustion air inlet pipe and one vent pipe) vent systems
and is in addition to "Section A - General Instructions - All
Units".
B2. Vertical vent systems terminate vertically (up).
B3. It is recommended to install a tee with drip leg and clean
out cap as shown in Figures 9.1 or 9.2.
B4. The combustion air and vent terminals must be Modine part
number:
• 5H072285-0001 (Item Code 27866) for 4" vent pipe
• 5H072285-0002 (Item Code 27868) for 6" vent pipe
B5. Vertical vents must terminate a minimum horizontal and
vertical distance from roof lines and adjacent walls or
obstructions. These minimum distances are outlined in
Figure 9.1 and Table 9.1 or Figure 9.2 and Table 9.2.
B6. The vent must terminate at least 1 foot above and 16
inches horizontally from the combustion air inlet.
B7. Once venting is complete, proceed to section titled
"Installation - Gas Connections".
Figure 9.1 - Vertical Venting - 2 Pipes Sloped Roof
LISTED VENT
TERMINAL
10 FEET OR LESS
TO ROOF PEAK
2 FEET MINIMUM
X
ROOF PITCH IS:
12"
X / 12
USE LISTED
THIMBLES
THROUGH ROOF
AND CEILINGS
MAINTAIN MINIMUM
CLEARANCE TO
COMBUSTIBLES
MINIMUM
Table 9.1 - Minimum Height from Roof to Lowest
Discharge Opening
Roof Rise Equivalent
"X" (in) Roof Pitch
0-10 Flat to 10/12
10-12 10/12 to 12/12
12-14 12/12 to 14/12
14-16 14/12 to 16/12
16-18 16/12 to 18/12
18-21 18/12 to 21/12
j Increase "H" as required to accommodate snow depth.
"H" FEET
MINIMUM PER
TABLE 8.1
16" MINIMUM
LISTED AIR
INLET TERMINAL
"H" FEET
MINIMUM PER
TABLE 8.1
ROOF
FLASHING
TEE WITH
12"
DRIP LEG AND
CLEANOUT CAP
Minimum Height
"H" (ft) j
3.00
4.00
5.00
6.00
7.00
8.00
Figure 9.2 - Vertical Venting - 2 Pipes Flat Roof
DISTANCE "D" TO
WALL OR ADJOINING
BUILDNG
"H" FEET MINIMUM
ABOVE WALL OR
ADJOINING
BUILDING PER
TABLE 7.2
*SIZE ACCORDING
TO EXPECTED
SNOW DEPTH
MAINTAIN MINIMUM
CLEARANCE TO
COMBUSTIBLES
Table 9.2 - Minimum Height Above Adjacent Wall
Less than 10 Feet Away
"D"
10 Feet or Less
Greater than 10 Feet
(continued next page)
5-594.10
LISTED VENT
TERMINAL
LISTED AIR
INLET TERMINAL
12"
MINIMUM
3 FEET
MINIMUM*
ROOF
FLASHING
USE LISTED
THIMBLE
THROUGH
CEILING
TEE WITH
12"
DRIP LEG AND
MINIMUM
CLEANOUT CAP
"H"
2 Feet Minimum
No Additional Height Required
9