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apart to prevent movement after installation.
16 - Select a wall termination point that will maintain
1/4” (6mm) rise per foot (305mm) slope of horizontal
run of vent pipe.
17 - For upward sloped vent, a condensate tee and
drain must be installed within the first 5 feet (2m) from
the unit heater to protect the appliance. If a flexible
condensate drain line is used, the drain line must
include a loop filled with water to prevent combustion
products from entering the structure. If the unit is shut
down for an extended period of time and will be
exposed to sub-freezing temperatures, the
condensate may freeze.
18 - Select a wall termination point that will maintain
1/4” rise per foot slope of horizontal run of vent pipe.
In areas where authorities having jurisdiction permit, a
downward slope of maximum 1/4” per foot is also
acceptable. Condensate drainage can be collected in
a tee pipe section (figure 4) with drain loop similar to
one used for upward slope vent, or allowed to drip
through the vent termination, if permitted by
authorities (figure 6).