MORTEX
PRODUCTS
INC
501
TERMINAL
RD
FORT
WORTH,
TX
76106
Page
24
Figure 27: Home Layout and Vent Clearances
Table 12: Vent Clearances
1. In accordance with the current CSA B149.1-00, Natural Gas and Propane Installation Code.
2. In accordance with the current ANSI Z223.1 / NFPA 54, National Gas Code.
† A vent shall not terminate directly above a side walk 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 clearance not specified in ANSI
Z223.1 / NFPA 54 or CSA B149.1-00
** Clearance in accordance with local installation codes, the requirements of the gas supplier and the manufacturer’s Installation Manual.
Any fresh air or make up inlet for dryer or furnace area is considered to be forced air inlet.
Avoid areas where condensate drainage may cause problems, such as above planters, patios, or adjacent to windows where steam may cause fogging.
A terminus of a vent shall be either:
a.
Fitted with cap accordance with the vent manufacturer’s Installation Instructions
b.
Or in accordance with the Installation Instructions for a special venting system.
Canadian Installations
¹
US Installation
²
A
Clearance above grade, veranda, porch, deck, or balcony
12
inches
(30
cm)
12
inches
(30
cm)
B
Clearance to window or door that may be opened
12
inches
(30
cm)
for
models
<100,000
BTUH
(30
kW),
36
inches
(91
cm)
for
models
>
100,000
BTUH
(30
kW)
4
Feet
(1.22
m)
C Clearance
to
permanently
closed
window
12
inches
(30
cm)
12
inches
(30
cm)
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
4
Feet
(1.22
m)
4
Feet
(1.22
m)
E Clearance
to
unventilated
soffit
12
Inches
12
Inches
F Clearance
to
outside
corner
12
Inches
12
Inches
G Clearance
to
inside
corner
6
feet
6
feet
(1.83
m)
6
feet
(1.83
m)
H Clearance
to
each
side
of
center
line
extended
above
meter/regulator
assembly
3
feet
(91
cm)
within
a
height
15
feet
(4.5
m)
above
the
meter/regulator
assembly
3
feet
(91
cm)
within
a
height
15
feet
(4.5
m)
above
the
meter/regulator
assembly
I Clearance
to
service
regulator
vent
outlet
3
feet
(91
cm)
3
feet
(91
cm)
J Clearance
to
non
‐
mechanical
air
supply
inlet
to
building
or
the
combustion
air
inlet
to
any
other
appliance
12
inches
(30
cm)
for
models
<100,000
BTUH
(30
kW),
35
inches
(91
cm)
for
models
>100,000
BTUH
(30
kW)
4
Feet
(1.22
m)
K Clearance
to
a
mechanical
supply
inlet
6
feet
(1.83
m)
3
feet
(91
cm)
above
if
within
10
feet
(3
cm)
horizontally
L Clearance
above
paved
sidewalk
or
paved
driveway
located
on
public
property
7
feet
(2.13
m)
7
feet
(2.13
m)
M Clearance
under
veranda,
porch,
deck,
or
balcony
12
inches
(30.4
cm)
12
inches
(30.4
cm)
Vent
Termination
from
any
Building
Surface
12
inches
(30.4
cm)
12
inches
(30.4
cm)
Above
anticipated
snow
depth
12
inches
(30.4
cm)
12
inches
(30.4
cm)
