Clearance To Combustibles - Field Controls SWG-3 Product Manual

SWG/CV POWER VENTER

CLEARANCE TO COMBUSTIBLES

If mounting the venting system near combustible materials, refer to
are based on an installation using single wall galvanized steel vent pipe. If manufactured double wall vent pipe is required or
used for the installation, clearance should be based on the vent pipe's rated clearance. Always check local code requirements for
code restrictions.
Routing of the vent system and clearances for the vent pipe
may be planned once the termination location is determined.
Route the vent pipe from the appliance to the venter using
as few elbows as possible. The horizontal section of the vent
pipe should have a slight upward slope from the appliance to
the venter. The vent pipe size (diameter) can be smaller than
a typical chimney vented system and still overcome the higher
pressure losses because the power venter mechanically
creates the required draft or air flow to vent the system.
For estimating the minimum vent pipe diameter for a gas
system, divide the BTU/hr. input of the heating equipment by
12,600 BTU/sq. in. For oil systems, multiply GPH by 140,000
BTU/GAL, then divide by 12,600 BTU/sq. in. This will give
the minimum cross-sectional area required. (See
area to diameter conversion.) For multiple equipment venting
systems, divide the total BTU/hr. input for all appliances by
9,300 BTU/sq. in. This will give you the minimum vent pipe
diameter needed for the common breach of the vent system.
As a rule of thumb, size the vent pipe to the outlet diameter of
the heating equipment for a single appliance venting system.
For multiple appliance venting systems, use the outlet diameter
of the largest unit and add 50%.
TABLE 4
NOMINAL CROSS-
PIPE SIZE
SECTIONAL AREA
3"
4"
5"
6"
7"
8"
9"
10"
12"
14"
6
Table 4 for
SQ. INCHES
7
13
20
28
38
50
64
79
1 13
154
Diagram A for allowable installation clearances. Clearances
DIAGRAM A
SINGLE PIPE SYSTEM
ALLOWABLE INLET ALLOWABLE INLET
CLEARANCE (B)
TEMPERATURE
400ºF OR LESS 3" MIN. 400ºF OR LESS
550ºF OR LESS 4" MIN. 550ºF OR LESS
550ºF OR LESS 3" MIN.* 550ºF OR LESS
* WITH GALVANIZED SHEET METAL LINER OR EQUIVALENT
METAL LINING FOR
550°F-400°F INPUT TEMP.
FLOOR JOIST
A
B-VENT
ELBOW
INPUT TEMP.
LOCATION
COMBUSTIBLE
MATERIAL
FLOOR JOIST
A B
INPUT TEMP.
LOCATION
OUTER PIPE
EXTENSION
END PIPE COVER
FROM SWG UNIT
B-VENT or
L-VENT
ELBOW
Customer Service:
DOUBLE PIPE SYSTEM
CLEARANCE (A)
TEMPERATURE
.5" MIN.
1" MIN.
.5" MIN.*
SQUARE HOLE
A
B THROUGH WALL
COMBUSTIBLE
B
MATERIAL
A
SWG SERIES
FLOOR
POWER VENTER
BLOCK
FOUNDATION
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