VII. Venting (continued)
Table 14: Direct Vent Terminal Clearances
Clearance above grade, veranda,
A
porch, deck, or balcony
Clearance to window or door that
B
may be opened
Clearance to permanently closed
C
window
Vertical clearance to ventilated soffit
located above the terminal within a
D
horizontal distance of 2 ft (61 cm)
from the center line of the terminal.
Clearance to unventilated soffit
E
F
Clearance to outside corner
G
Clearance to inside corner
Clearance to each side of center
H
line extended above meter/regulator
assembly
Clearance to service regulator vent
I
outlet
Clearance to nonmechanical air
supply inlet to building or the
J
combustion air inlet to any other
appliance
Clearance to a mechanical air
K
supply inlet
Clearance above paved sidewalk or
L
paved driveway located on public
property
Clearance under veranda, porch
M
deck, or balcony
*
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.
22
Canadian Installations
18 in. (46 cm)
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)
*
*
*
*
*
3 ft (91 cm) within a height of
15 ft (4.6 m)
3 ft (91 cm)
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)
6 ft (1.83 m)
7 ft (2.13 m) †
12 in (30 cm) ‡
NOTICE
NOTICE
US Installations
1
12 in (30 cm)
6 in (15 cm) for appliances
≤ 10,000 Btuh (3 kW), 9 in (23
cm) for appliances > 10,000 Btuh
(3 kW) and ≤ 50,000 Btuh (15
kW), 12 in (30 cm) for appliances
> 50,000 Btuh (15 kW)
6 in (15 cm) for appliances ≤
10,000 Btuh (3 kW), 9 in (23 cm)
for appliances > 10,000 Btuh (3
kW) and ≤ 50,000 Btuh (15 kW),
12 in (30 cm) for appliances >
50,000 Btuh (15 kW)
3 ft (91 cm) above if within
10 ft (3 m) horizontally
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*
AMP 400-1000L I&O Manual
2
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