Installation & Operation Manual
Table 4B
Direct Vent Terminal Clearances (continued)
Figure 4-4B
Other than Direct Vent Terminal Clearances
4
Sidewall direct venting
(continued)
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)
6 in (15 cm) for appliances < 10,000 Btuh
(3kW), 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) and not exceeding > 150,000 Btuh
(30 kW)
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
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