Vent Pipe Termination - A.O. Smith 120 Series Instruction Manual

TERMINATION CLEARANCES SIDEWALL POWER VENT
Vent terminal clearances for "Power Vent" installations. Power Vent configurations use room air for combustion.
Clearance above grade, veranda,
A
porch, deck or balcony
Clearance to window or door
B
that may be opened
Clearance to permanently
C
closed window
Vertical clearance to ventilated
soffit located above the terminal
D
within a horizontal distance of 2
feet (61 cm) from the center line
of the terminal
E
Clearance to unventilated soffit
F
Clearance to outside corner
G
Clearance to inside corner
2 In accordance with the current ANSI Z223.1/NFPA 54, National Fuel Gas Code.
† A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings.
Where it may cause hazardous frost or ice accumulations on adjacent property surfaces.
‡ Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
* Clearance in accordance with local installation codes and the requirements of the gas supplier and the manufacturer's installation instructions.

VENT PIPE TERMINATION

The first step is to determine where the vent pipe will terminate.
See Figures 15, 20 and 21. The vent may terminate through a
sidewall as shown in Figure 20 or through the roof as shown in
Figure 21.
The vent system must terminate so that proper clearances are
maintained as cited in local codes or the current edition of the
National Fuel Gas Code.
Instructions on proper installation through a sidewall are provided in
FIGURE 15.
US INSTALLATIONS
2
12 inches (30 cm)
4 feet (1.2 m) below or to side of
opening; 1 foot (30 cm) above
opening
12 inches (30 cm)*
12 inches (30 cm)*
12 inches (30 cm)*
M
2 feet (60 cm)*
18 inches (45 cm)*
Clearance to each side of center
H
line extended above meter/regulator
assembly
Clearance to service regulator vent
I
outlet
Clearance to a non mechanical air
J
supply inlet into building or combustion
air inlet to any other appliance
Clearance to a mechanical air supply
K
inlet
Clearance above paved sidewalk or
L
paved driveway located on public
property
Clearance under veranda, porch, deck,
or balcony
Figure 15.
Plan the vent system layout so that proper clearances are
maintained from plumbing and wiring.
Vent pipes serving power vented appliances are classified
by building codes as "vent connectors". Required clearances
from combustible materials must be provided in accordance
with information in this manual under LOCATING THE NEW
WATER HEATER and INSTALLING THE WATER HEATER, and
with the National Fuel Gas Code and local codes.
19
US INSTALLATIONS
2
Clearance in accordance with
local installation codes and the
requirements of the gas supplier
Clearance in accordance with
local installation codes and the
requirements of the gas supplier
4 feet (1.2 m) below or to side of
opening; 1 foot (30 cm) above
opening
3 feet (91 cm) above if within 10 feet
(3 m) horizontally
7 feet (2.13 m)
12 inches (30 cm) ‡