| VENT TERMINAL | AIR SUPPLY INLET | AREA WHERE TERMINAL IS NOT PERMITTED | ||
|
|
|
|
|
|
|
|
| Canadian Installations1 |
| US Installations2 |
A = | Clearance above grade, veranda, porch, | 12 inches (30 cm) |
| 12 inches (30 cm) | |
| deck, or balcony |
|
|
|
|
|
|
|
| ||
B = | Clearance to window or door that may be | 6 inches (15 cm) for appliances 10,000 | 4 feet (1.2 m) below or to side of opening; | ||
| opened |
| Btuh (3 kW), 12 inches (30 cm) for | 1 foot (300 mm) above opening | |
|
|
| appliances > 10,000 Btuh (3 kW) and |
| |
|
|
| 100,00 Btuh (30 kW), 36 inches (91 cm) |
| |
|
|
| for appliances >100,00 Btuh (30 kW) |
| |
|
|
|
|
| |
C = | Clearance to permanently closed window | * |
| * | |
D = | Vertical clearance to ventilated soffit |
|
|
|
|
| located above the terminal 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 |
| * |
| * |
H = | Clearance to each side of center line |
| 3 feet (91 cm) within a height 15 feet | * | |
| extended above meter/regulator assembly | above the meter/regulator assembly | |||
|
| ||||
I = | Clearance to service regulator vent outlet | 3 feet (1.83 m) |
| * | |
J = | Clearance to nonmechanical air supply inlet | 6 inches (15 cm) for appliances 10,000 | 4 feet (1.2 m) below or to side of opening; | ||
| to building or the combustion air inlet to any | Btuh (3 kW), 12 inches (30 cm) for | 1 foot (300 mm) above opening | ||
| other appliance |
| appliances > 10,000 Btuh (3 kW) and |
| |
|
|
| 100,00 Btuh (30 kW), 36 inches (91 cm) |
| |
|
|
| for appliances >100,00 Btuh (30 kW) |
| |
|
|
|
|
| |
K = | Clearance to a mechanical air supply inlet | 6 feet (1.83 m) |
| 3 feet (91 cm) above if within 10 feet | |
|
|
|
|
| (3 m) horizontally |
|
|
|
|
| |
L = | Clearance above paved sidewalk or paved | 7 feet (2.13 m) † |
| 7 feet (2.13 m) | |
| driveway located on public property |
|
|
|
|
|
|
|
|
| |
M = | Clearance under veranda, porch deck, or | 12 inches (30 cm) ‡ |
| * | |
| balcony |
|
|
| |
|
|
|
|
| |
|
|
|
|
|
|
1In accordance with the current CSA B149.1 Natural Gas and Propane Installation Code
2In 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.
‡ Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
*For clearances not specified in ANSI Z223.1 / NFPA 54 or CSA B149.1, one of the following statement shall be included:
“Clearance in accordance with local installation codes, and the requirements of the gas supplier and the
manufacturer’s installation instructions.”
Figure 20. Vent Termination Clearances for Other Than Direct Vent Furnaces
24