AMPW 400-1000L I&O Manual
25
. Venting
(continued)
Table 15: Other than Direct Vent Terminal Clearances
Canadian Installations
1
US Installations
2
A
Clearance above grade, veranda,
porch, deck, or balcony
12 in (30 cm)
12 in (30 cm)
B
Clearance to window or door that
may be opened
6 in (15 cm) for appliances ≤
10,000 Btuh (3 kW), 12 in (30
cm) for appliances > 10,000 Btuh
(3 kW) and ≤ 100,000 Btuh (30
kW), 36 in (91 cm) for appliances
>100,000 Btuh (30 kW)
4 ft (1.2 m) below or to side of
opening; 1 ft (300 mm) above
opening
C
Clearance to permanently closed
window
*
*
D
Vertical clearance to ventilated soffit
located above the terminal within a
horizontal distance of 2 ft (61 cm)
from the center line of the terminal.
*
*
E
Clearance to unventilated soffit
*
*
F
Clearance to outside corner
*
*
G
Clearance to inside corner
*
*
H
Clearance to each side of center
line extended above meter/regulator
assembly
3 ft (91 cm) within a height 15 ft
(4.6 m)
*
I
Clearance to service regulator vent
outlet
3 ft (91 cm)
*
J
Clearance to nonmechanical air
supply inlet to building or the
combustion air inlet to any other
appliance
6 in (15 cm) for appliances ≤
10,000 Btuh (3 kW), 12 in (30
cm) for appliances > 10,000 Btuh
(3 kW) and ≤ 100,000 Btuh (30
kW), 36 in (91 cm) for appliances
>100,000 Btuh (30 kW)
4 ft (1.2 m) below or to side of
opening; 1 ft (300 mm) above
opening
K
Clearance to a mechanical air
supply inlet
6 ft (1.83 m)
3 ft (91 cm) above if within
10 ft (3 m) horizontally
L
Clearance above paved sidewalk or
paved driveway located on public
property
7 ft (2.13 m) †
7 ft (2.13 m) for mechanical draft
systems (Category I appliances).
Vents for Category II and IV
appliances cannot be located
above public walkways or other
areas where condensate or vapor
can cause a nuisance or hazard
M
Clearance under veranda, porch
deck, or balcony
12 in (30 cm) ‡
*
* Clearance in accordance with local codes and the requirements of the gas supplier.
† A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family
dwellings and serves both dwellings.
‡ Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
Notes:
1) In accordance with the current CSA B149.1, Natural Gas and Propane Installation Code
2) In accordance with the current ANSI Z223.1/NFPA 54, National Fuel Gas Code
3) If locally adopted installation codes specify clearances different than those illustrated, then the most stringent
clearance shall prevail.
