W415-3101 / B / 01.09.23
27
IOM
FIGURE 14A - DIRECT VENT TERMINAL CLEARANCES
D
E
B
C
F
B
B
A
M
K
B
J
I
B
B
H
Fixed
Closed
Fixed
Closed
Openable
= Vent Terminal
= Air Supply Inlet
= Area where terminal is not permitted
Openable
Legend:
A
G
Combustible &
Non-combustible
L
Canadian Installations
US Installations
A =
Clearance above grade, veranda, porch,
desk, or balcony
12in (30cm)
B =
Clearance to window or door that may
be opened
6in (15cm) for appliances
≤
10’000Btuh
(3kW), 12in (30cm) for appliances
>10’000Btuh (3kW) and
≤
100’00Btuh
(30kW), 36in (91cm) for appliances >
100’00Btuh (30kW)
6in (15cm) for appliances
≤
10’000Btuh
(3kW), 9in (23cm) for appliances
>10’000Btuh (3kW) and
≤
50,000Btuh
(15kW), 12in (91cm) for appliances >
50’00Btuh (15kW)
C =
Clearance to permanently closed
window
12in (30cm)
12in (30cm)
D =
Vertical clearance to ventilated so
ffi
t
located above the terminal within a
horizontal distance of 2 feet (61cm) from
the center line of the terminal.
18in (46cm)
18in (46cm)
E =
Clearance to unventilated so
ffi
t
12in (30cm)
12in (30cm)
F =
Clearance to outside corner
6in (15cm)
6in (15cm)
G =
Clearance to inside corner
6in (15cm)
6in (15cm)
H =
Clearance to each side of center line ex-
tended above meter/regulator assembly
3ft (91cm) within a height 15ft (4.5m) above the meter / regulator
assembly
I =
Clearance to service regulator vent
outlet
3ft (91cm)
J =
Clearance to non mechanical air supply
inlet to building or the combustion air
inlet to any other appliance
6in (15cm) for appliances
≤
10’000Btuh
(3kW), 12in (30cm) for appliances
>10’000Btuh (3kW) and
≤
100’00Btuh
(30kW), 36in (91cm) for appliances >
100’00Btuh (30kW)
6in (15cm) for appliances
≤
10’000Btuh
(3kW), 9in (23cm) for appliances
>10’000Btuh (3kW) and
≤
50,000Btuh
(15kW), 12in (91cm) for appliances >
50’00Btuh (15kW)
K =
Clearance to a mechanical air supply
inlet
6ft (1.83m)
3ft (91cm) above if within 10ft (3m)
horizontally
L =
Clearance above paved sidewalk or
paved driveway located on public
property
7ft (2.13m)†
M+ =
Clearance under veranda, porch, deck,
or balcony
>12in (30cm)‡
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.
† 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 fl oor.
Summary of Contents for WSX-N Series
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