W415-1068 / B / 01.02.14
12
EN
3.3 MINIMUM AIR TERMINAL LOCATION CLEARANCES
INSTALLATIONS
CANADA
U.S.A.
A
12” (304.8mm)
12” (304.8mm)
Clearance above grade, veranda porch, deck or balcony.
B
12” (304.8mm)
Δ
9” (228.6mm)
Δ
Clearance to windows or doors that open.
C
12” (304.8mm)*
12” (304.8mm)*
Clearance to permanently closed windows.
D
18”
(457.2mm)**
18” (457.2mm)**
Vertical clearance to ventilated sof
fi
ts located above the terminal within a horizontal distance
of 2’ (0.6m) from the centerline of the terminal.
E
12”
(304.8mm)**
12” (304.8mm)** Clearance to unventilated sof
fi
t.
F
0” (0mm)
0” (0mm)
Clearance to an outside corner wall.
G
0” (0mm)***
0” (0mm)***
Clearance to an inside
non
-combustible corner wall or protruding
non
-combustible obstructions (chim-
ney, etc.).
2” (50.8mm)***
2” (50.8mm)***
Clearance to an inside combustible corner wall or protruding combustible obstructions (vent
chase, etc.).
H
3’ (0.9m)
3’ (0.9m)****
Clearance to each side of the centerline extended above the meter / regulator assembly to a
maximum vertical distance of 15’ (4.6m).
I
3’ (0.9m)
3’ (0.9m)****
Clearance to a service regulator vent outlet.
J
12” (304.8mm)
9” (228.6mm)
Clearance to a non-mechanical air supply inlet to the building or a combustion air inlet to any other
appliance.
K
6’ (1.8m)
3’ (0.9m)
Clearance to a mechanical air supply inlet.
L
7’ (2.1m)‡
7’ (2.1m)****
Clearance above a paved sidewalk or paved driveway located on public property.
M
12”
(304.8mm)††
12”
(304.8mm)****
Clearance under a veranda, porch, deck or balcony.
N
16” (406.4mm)
16” (406.4mm)
Clearance above the roof.
O
2’ (0.61m)†*
2’ (0.61m)†*
Clearance from an adjacent wall including neighbouring buildings.
P
8’ (2.4m)
8’ (2.4m)
Roof must be
non
-combustible without openings.
Q
3’ (0.9m)
3’ (0.9m)
See chart for wider wall dimensions.
R
6’ (1.8m)
6’ (1.8m)
See chart for deeper wall dimensions. The terminal shall not be installed on any wall that has
an opening between the terminal and the open side of the structure.
Δ
The terminal shall not be located less than 6 feet (1.8m) under a window that opens on a horizontal plane in a structure with three walls and a roof.
*
Recommended to prevent condensation on windows and thermal breakage
**
It is recommended to maximize the distance to vinyl clad sof
fi
ts.
***
The periscope requires a minimum 18” (457.2mm) clearance from an inside corner.
****
This is a recommended distance. For additional requirements check local codes.
†
3 feet (0.91m) above if within 10 feet (3.1m) horizontally.
‡
A vent shall not terminate where it may cause hazardous frost or ice accumulations on adjacent property surfaces.
††
Permitted only if the veranda, porch, or deck is fully open on a minimum of two sides beneath the
fl
oor.
†*
Recommended to prevent recirculation of exhaust products. For additional requirements check local codes.
12.3C
R
Q
M
G
P
COVERED BALCONY APPLICATIONS
Q
MIN
R
MAX
MAX
R
= 3 feet
(0.9m)
= 2 x
IHHW
(4.6m)
Q
ACTUAL
