Installation Instructions

12
AmeriVent Round and Oval Gas Vent
Installation Instructions
Flat to 7/12 1.00 feet
over 7/12 to 8/12 1.50 feet
over 8/12 to 9/12 2.00 feet
over 9/12 to 10/12 2.50 feet
over 10/12 to 11/12 3.25 feet
over 11/12 to 12/12 4.00 feet
over 12/12 to 14/12 5.00 feet
over 16/12 to 18/12 6.00 feet
over 18/12 to 20/12 7.00 feet
over 20/12 to 21/12 8.00 feet
Table 7
Roof Pitch
Minimum Height
AmerVent Cap 12" and Smaller
Gas Vent Termination Table
CAUTION
WHERE HEAVY SNOWFALL OCCURS, THE CAP
SHOULD BE INSTALLED TO MEET THE ABOVE
MINIMUM HEIGHT REQUIREMENTS ABOVE THE
AVERAGE SNOW DEPTH.
The vent termination should not be less than 8 ft.
from a vertical wall.
8' MIN.
SEE GAS VENT
TERMINATION TABLE
AmeriVent Caps larger than 12" must be located at least 2 feet above
the highest point where they pass through a roof and at least 2 feet
higher than any portion of a building within a horizontal distance of 10
feet.
10' OR LESS
2'
MIN.
2' MIN.
2' MIN.
WALL OR
PARAPET
NOTE:
NO HEIGHT ABOVE
PARAPET REQUIRED
WHEN DISTANCE
FROM WALLS OR
PARAPET IS MORE
THAN 10’.
Figure 21
Figure 20
AmeriVent Caps 12" and Smaller
AmeriVent Caps 3" thru 30"
Figure 22
A cap or chimney housing offers resistance to the entrance
of rain, snow and debris, as well as birds, and will minimize
the effect of wind on the vent. It will protect the vent from
down drafts due to a wind that impinges directly upon the
vent.
However, no vent cap, cowl, or top can overcome the
adverse effect of a region of high static pressure around the
vent terminal or the effect of an interior region of low
pressure. Regions of high static pressure around the vent
terminal can be avoided by following the general rule for
the vent termination given previously. Low or negative
interior pressures in the building may be caused by (1)
failure to provide for combustion air, (2) excessive use of
exhaust fans, and (3) tight construction resulting in the lack
of infiltration air.
1. To ensure a waterproof roof structure, use the
appropriately sized flashing and storm collar where the
vent penetrates the roof. Place the Storm Collar over
the vent until it is level. Apply a thick horizontal ring of
nonhardening, high-temperature mastic, such as
silicone, around the vent at the top of the Storm Collar.
2. Vents in excess of 5 feet above the roof should be
securely guyed to prevent unnecessary movement.
Attach guying to the vent. Never attach guying to the
cap.
3. To prolong life and appearance of galvanized steel
parts located outside, use proper painting procedure.
a. Remove oil and dirt with a solvent.
b. Paint with primer specifically recommended for
adhesion to galvanized steel.
c. Apply finish coat.