Vent Termination
A. Clearance above grade, veranda, porch, deck, or balcony 12
inches (30cm) minimum [1].
B. Clearance to window or door that may be opened. 12 inches (30cm)
minimum for appliances 100 000 Btuh (30 kW) and lower, in Canada.
9 inches [2] (23cm) for appliances 50 000 Btuh and lower, in USA.
C. Clearance to permanently closed window minimum 12 inches
(30cm) recommended to prevent condensation on window, in
Canada. 9 inches [2] (23cm) for appliances 50 000 Btu’s and
lower, in USA.
D. Vertical clearance to ventilated soffit or vinyl soffit / siding located
above the termination within a horizontal distance of 2 feet
(60cm) from the center line of the termination. 18 inches (46cm)
minimum [5].
E. Clearance to unventilated soffit 12 inches (30cm) minimum.
F. Clearance under veranda, porch, deck or balcony 12 inches[1]
(30cm) minimum [4].US [5]
G. Clearance from a perpendicular inside wall or outer corner to
the edge of the vent terminal plate is 3” (minimum).
H. Clearance to each side of center line extended above
meter/regulator assembly 3 feet (91cm) within a height 15
feet (4.5m) above the meter/regulator assembly.
I. Clearance to service regulator vent outlet 3 feet (91cm)
minimum
[1]. US[5]
J. Clearance to non-mechanical air supply inlet to building or the
combustion air inlet to any other appliance: In Canada, 6
inches (15cm) for appliances ≤10,000 Btuh (3kW), 12
inches[1] (30cm) minimum for appliances >10,000 Btuh (3kW)
and
≤100,000 Btuh (30kW), 36 inches (91cm) for appliances
>100,000 Btuh (30kW). In the USA, 6 inches[2] (15cm) for
appliances ≤10,000 Btuh (3kW), 9 inches (23cm) for
appliances
>10,000 Btuh (3kW) and ≤50,000 Btuh (15kW), 12
inches
(30cm) for appliances >50,000 Btuh (15kW).
K. Clearance to a mechanical air supply inlet 6 feet (1.8m) mini
mum [1], in Canada. In USA, 3 feet (91cm) above if within10
feet (3m) horizontally [2].
L. Clearance above paved sidewalk or a paved driveway
located
on public property 7 feet (2.1m) minimum [3].
M. Clearance above highest point of exit on roof 18 inches
(45cm).
N. Clearance to perpendicular wall 24 inches (60 cm).
(Recommended to prevent re-circulation of exhaust products.
For additional requirements check local codes.)
O.
A moisture-exhaust duct shall not terminate within 3 ft (1
m) in any direction of a service regulator or fresh-air
intake.
NOTE: Clearances are to the edge of terminal plate, add 6-
3/4” to clearances to arrive at center line.
NOTE: Local Codes or Regulations may require different
clearances.
Termination
It is imperative that the vent termination be located observing the
minimum clearances as shown. There must not be any obstruction
such as bushes, garden sheds, fences, decks or utility buildings
within 24” from the front of the termination plate.
Do not locate termination where excessive snow or ice build-up
may occur. Be sure to check vent termination area after snow falls
and clear to prevent accidental blockage of venting system. When
using snow blowers, make sure snow is not directed towards vent
termination area.
Venting terminal shall not be recessed into a wall or siding. If
finishing the outside wall with vinyl or wood siding it is
recommended that a Siding Shield be installed, Part Number
ZDVSSLR.
1.
In accordance with the current CSA B149.1, Natural Gas and
Propane Code.
2.
In accordance with the current ANSI Z223.1/NFPA 54,
National Fuel Gas Code.
3.
A vent shall not terminate where it may cause hazardous
frost or ice accumulations on adjacent property surfaces.
4.
Permitted only if veranda, porch, deck, or balcony is fully
open on a minimum of two sides beneath the floor.
5.
Clearance in accordance with local installation codes and the
requirements of the gas supplier.
WARNING:
A
HORIZONTAL VENT
CERTIFIED GUARD
(SAFETY CAGE) IS
AVAILABLE WHEN
REQUIRED BY LOCAL
CODES.
Notes:
1) Clearances are to the edge of the terminal plate.
Add 6-3/4” to clearances to arrive at centerline.
2) Local codes or regulations may require different
clearances.
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