10
Installation of Type B-W Gas Vent
1. Cut out the ceiling plate at the floor level above the
heater flush with studs in space where Vent is to be
installed.
2. Nail one Ameri-Vent Plate Spacer (40PS), (A), across
cut out area in ceiling plate - see Fig. 16.
3. Snap Hold Down Plate (4OHD), (B), onto bottom end
of Ameri-Vent pipe as shown in Fig. 16. Install Vent
Section in position. Use two No. 8 binder head sheet
metal screws to attach Hold Down Plate firmly to Furnace
header plate through pre-punched holes.
4. Nail second Ameri-Vent Plate Spacer across cutout
ceiling plate as shown in Fig. 16.
5. If the Vent is to continue additional stories within a 2x4
stud space, install Firestop Spacers at the second and
subsequent ceiling levels as shown in Fig. 17.
6. After passing through the last Firestop Spacer, the Vent
may be finished with either round or oval Ameri-Vent
fittings, flashings and Ameri-Cap. (Round pipe, fittings,
flashings and vent caps cost less than corresponding oval
parts.)
Attic Insulation Shield
In some areas the building code requires the use of an
attic insulation shield (AVS) on single story Type B-W
installations.
Termination of Vent Structure
The Ameri-Vent Gas Vent is available for most Models
and sizes in two styles of Termination Tops, Ameri-Cap
and Universal Cap. The Ameri-Cap is a lock neck design
with the same lock as the female end of the Vent sections.
The Universal Cap is designed to fit inside the inner wall
of the vent sections.
American Metal Products 12" and smaller Gas Venting
Systems using either the Ameri-Cap or the Universal
Cap, may terminate in accordance with Table 6 and
Figs. 18 & 20.
Multi-Story
Type B-W
Installations
AT SECOND AND
SUBSEQUENT CEILING LEVELS
USE 40FS FIRESTOP SPACERS.
AT FIRST CEILING LEVEL
USE 40PS CEILING
PLATE SPACERS.
A
B
Type B-W
Installation
Roof Pitch
Minimum Height
Flat to
7/12
1.0 feet
over
7/12 to 8/12
1.5 feet
over
8/12 to 9/12
2.0 feet
over 9/12
to
10/12
2.5
feet
over
10/12 to 11/12
3.25 feet
over
11/12 to 12/12
4.0 feet
over
12/12 to 14/12
5.0 feet
over
16/12 to 18/12
6.0 feet
over
18/12 to 20/12
7.0 feet
over
20/12 to 21/12
8.0 feet
Table 6
Ameri-Cap 12" and Smaller
Gas Vent Termination Table
FIG. 17
FIG. 16
