16
SST Extreme X & SST Extreme S MODULATING I&O Manual
RD: JAN 2022
RL: 1A
Horizontal vent through the sidewall (Category III)
:
◼
When installed with a horizontal vent through a sidewall, this heater is a Category III appliance,
and venting materials must be approved for Category III applications.
◼
All vent must be installed in accordance with local codes or, in the absence of local codes, with
the
National Fuel Gas Code,
ANSI Z223.1/NFPA 54; or the
Natural Gas and Propane Installa-
tion Code
CSA B149.1.
◼
All vent must installed in accordance with these instructions, and the instructions of the vent
manufacturer.
◼
Do not mix vent components from different manufacturers in the vent system
◼
A single wall vent system may use a single continuous section of double wall vent pipe to pass
through an exterior wall.
◼
Any horizontal portion of the flue vent system must slope downwards away from the heater a
minimum of 1/4" per foot run toward the vent terminal.
◼
All vent pipe from a single heater must be
4”
diameter; common vent pipe for two heaters must
increase to
6”
at the point of connection of individual
4”
vents
◼
Use approved 4" (JA
-
0528
-
XX) horizontal wall vent terminal or an approved high
-
wind termina-
tion cap
◼
Installation of the vent must prevent blockage by snow and protect building materials from deg-
radation by flue gases.
◼
Install termination cap a minimum of 18 inches from the outside wall to the inside edge of ter-
minal opening to alleviate back pressure caused by turbulent wind conditions (See Fig. 8). This
also ensures flue gases are directed away from the structure to protect building materials from
degradation by the exhausted flue gases.
◼
At most two 90° elbows can be installed in a horizontal vent
◼
A horizontal flue vent will not terminate less than 1 ft above grade level, unless its location is
adjacent to public walkways, then it must not terminate less than 7 ft above the walkway.
◼
Clearance below a combustible overhang or soffit:
•
As indicated in FIGURE 8 for approved terminations: 4" JA
-
0528
-
XX
•
For other approved terminations: Will terminate 3 ft or more below a combustible soffit or
overhang.
◼
A horizontal vent termination must be a minimum of 6 feet from an inside corner formed by two
exterior walls.
◼
A venting system shall be securely supported by noncombustible hangers suitable for the
weight of the materials.
◼
A slip joint in the horizontal section of a venting system shall be secured with quantity 3 x #8 x
1/2”
sheet metal screws to prevent sagging.
◼
Seal single
-
wall vent seams and joints with Dow Corning 736 Heat Resistant Sealant 600°F
(315°C) or equivalent, or follow the instructions of the vent manufacturer for sealing vent pipe
connections
USA and Canada specific requirements for horizontal vent are on the next page
