SWG Power Venter

Planning the Vent System

Location of the termination of the venting system should comply with the National Fuel Gas Code, ANSI Z223.1, manufacturer’s recommendations, and/or applicable local codes. See diagram for typical terminal locations.

A. The exit termination of a mechanical draft system must not be less than 7' above grade when located adjacent to a public walkway.*
B. The venting systems, with the exception of direct vent appliances, must terminate at least 4' below, 4' horizontally, or 1' above any door, window or gravity air inlet into the building.
C. A venting system must terminate at least 3' above any forced air inlet located within 10'.
D. The bottom of the vent terminal must be located at least 1' above finished grade.**
E. The vent termination should not be mounted directly above or within 3' horizontally from an oil tank vent or gas meter (not shown in diagram).
F. The vent termination point must not be installed closer than 3' from an inside corner of an L-shaped structure.
G. For basement installations where a window well must be used or in installations where the vent terminal cannot be mounted to maintain the minimum 12" clearance above grade, use a Field Vent Riser™. The Vent Riser ensures the vent termination is above grade or the snow line and is in compliance with local codes (not shown in diagram).

planning the vent system
*10" or larger should be 10' minimum above public walkway. **10" or larger should be 4' above finished grade.

Calculating Equivalent Feet of a Vent System

1. Determine the total equivalent feet for each type of fitting used in the venting system from Tables 2 and 3.
2. Calculate the total feet for the straight lengths of pipe.
3. Add the equivalent feet of the fittings to the total amount of feet of straight length pipe. This will approximate the total equivalent feet of the vent system.
4. Find your total equivalent feet in Table 1 to determine the proper model for your installation.
Example: System Pipe Size= 6"
Step 1 2-90° Elbows (6")= 22 Ft.
Step 2 10-2 Ft. Lengths of 6" Pipe= 20 Ft.
Step 3 6" to 4" reducer= 4 Ft.
Step 4 Total Equivalent Feet= 22 Ft. + 20 Ft. + 4 Ft.= 46 Ft.

Table 2-Equivalent Feet for Vent Pipe Fitting
Vent Pipe Fittings Vent Pipe Diameter
3" 4" 5" 6" 7" 8" 9" 10" 12" 14"
Tee 19 25 31 38 44 50 56 63 75 89
Y-Connection 10 13 16 20 23 26 29 32 39 45
90° Elbow 5 7 9 11 12 14 16 18 21 25
45° Elbow 3 4 4 5 6 7 8 9 10 13
Table 3-Equivalent Feet for a Reducer/Increaser
Large Pipe Size Small Pipe Size
3" 4" 5" 6" 7" 8" 9" 10" 12" 14"
3" 0
4" 2 0
5" 4 2 0
6" 5 4 2 0
7" 6 5 4 1 0
8" 7 7 6 3 2 0
9" 7 8 7 5 4 2 0
10" 8 8 8 6 6 4 2 0
12" 8 10 10 8 9 8 6 4 0
14" 9 10 12 10 12 11 9 8 3 0
16" 9 11 12 11 14 13 13 11 8 3
18" 9 11 13 12 15 15 15 14 11 7
20" 9 12 14 13 16 17 17 17 15 11
To calculate the footage, add the lengths of all the straight lengths of vent pipe to the equivalent feet of all the vent pipe fittings, such as tees, elbows, and reducers.


SWG Super Lube

• Oil motor and fan shaft with SWG Super Lube annually
• Works in conditions of -40° to 300° (F)
• Synthetic lubricant which maintains specified viscosity
• Use of any other lubricant may cause premature failure

SWG Superlube
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