2
Venting
Installation & Operation Manual
32
Canadian Installations¹
US Installations²
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
(3kW), 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 installation 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 he fl oor.
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
Table 2G
Other than Direct Vent Terminal Clearances
