VENT TERMINATION ON SINGLE−WALL VERTICAL VENT RUNS
SINGLE−WALL VENT PIPE WITH
SINGLE−WALL VENT PIPE WITH
SINGLE−WALL TERMINATION
DOUBLE−WALL (TYPE B−1) TERMINATION
ROOF FLASHING
ROOF PITCHED
FROM 0" TO 45"
ROOF FLASHING
ROOF PITCHED
FROM 0" TO 45"
12" MAX
2” CLEARANCE
THIMBLE
SEAL JOINT BETWEEN SINGLE−WALL VENT AND B" VENT TERMINATION
AND THE OPEN SPACE BETWEEN THE SINGLE WALL VENT PIPE AND
THE OUTER PIPE OF THE B" VENT TERMINATION.
CLEARANCE TO BE
AS SPECIFIED ON
TYPE B" VENT PIPE.
FIGURE 3
7 − The vent pipe must extend at least 3 feet (1m)
above the highest point where it passes through a
roof of a building. The vent must also extend at
least two feet higher than any part of a building
within a horizontal distance of 10 feet (3.05 m)
unless otherwise specified by the ANSI Z223.1 or
CSA−B149 installation compliance codes. The
vent must extend at least 5 feet (1.53 m) above
the highest connected equipment flue collar.
TABLE 3
MAXIMUM HORIZONTAL VENT CONNECTOR AND
HORIZONTAL VENT PIPE LENGTHS
HED−75 through
HED−200 through
No. of
−150
−300
Elbows
ft
m
ft
m
1
25
7.6
35
10.7
2
20
6.1
30
9.1
3
15
4.6
25
7.6
4
10
3.0
20
6.1
5
5
1.5
15
4.6
6
−−
−−
10
3.0
7
−−
−−
5
1.5
8−
When the length of a single-wall vent, including
elbows, exceeds the length shown in table 4, the
vent shall be insulated along its entire length with a
minimum of 1/2" thick foil faced fiberglass 1–1/2#
density insulation.
TABLE 4
MAXIMUM LENGTH UNINSULATED VENT CONNECTOR
HORIZONTAL VENTING
NOTE
− Common venting is not allowed when
horizontally venting the duct heater.
If the HED duct heater is to be horizontally vented, a
positive pressure may be created in the vent. The duct
heater, when installed with horizontal venting, will
perform as a category III appliance.
1 −
Special vent materials approved for use with
Category III appliances may be used with these
units.
Refer to table 7 for venting components.
2 − If possible, do not terminate the horizontal vent
through a wall that is exposed to prevailing wind.
Exposure to excessive winds can affect unit
performance. If such a termination is necessary,
use a wind block to protect the vent termination
from direct winds.
3 − Vent termination must be free from obstructions
and at least 12" (30.5 cm) above grade level and
maximum snow height.
4 − Do not terminate vent directly below roof eaves or
above a public walkway, or any other area where
condensate dripping may be troublesome and
may cause some staining. Avoid windows where
steam may cause fogging or ice buildup.
5 − Minimum clearance for horizontal vent termination
from any door, window, gravity air inlet, gas or
electric meter, regulators, and relief equipment is
4 feet (1m) for United States installations.
In Canada, horizontal vent termination must have
a minimum 6-foot horizontal clearance from gas
and electric meters and relief devices.
(INCLUDING ELBOWS)
Model
ft
m
HED−75
15
4.57
HED−100 THROUGH 300
N/A*
N/A*
*Not applicable for larger units. Maximum length of uninsulated vent
is equal to maximum allowable vent length from table 2.
Refer to latest editions of the ANSI Z223.1 or
CSA−B149 for installation compliance codes and
with local authorities with jurisdiction.
6 − Vent termination must be a minimum of 4 feet
(1.2m) horizontally from any soffit or under-eave
vent.
7
