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jurisdiction permit, a downward slope of maximum ¼”
per foot is also acceptable. In such cases, the vent
must be listed special vent for Category III appliances
or single wall vent pipe constructed of number 26 GSG
(0.46 mm) galvanized steel or equivalent grade
stainless steel. Seal single wall vent material according
to the section
A-General Recommendations and
Requirements
. Condensate drainage can be collected
in a tee pipe section (Figure 4) or allowed to drip
through the vent termination, if permitted by local
authorities (Figure 5).
5- For upward sloped vent a condensate tee and drain
must be installed within the first 5’ (1.5 m) 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.
FIGURE 3
CONDENSATE DRAIN THROUGH TEE PIPE AND DRAIN LOOP
FLUE TRANSITION
(PROVIDED)
INDUCED
DRAFT
BLOWER
VENT
TERMINATION
TEE
12" (30.5CM)
MINIMUM ABOVE
HIGHEST SNOWFALL
DRAIN LOOP WITH WATER
TRAP (TO CONDENSATE DRAIN)
LISTED THIMBLE
THROUGH COM-
BUSTIBLE WALL
MAY BE SINGLE WALL (26 GSG) GALV. OR EQUIV. STAINLESS STEEL SEALED ACCORDING
TO THESE INSTALLATION INSTRUCTIONS. SLOPE:+ 1/4 INCH FOR 1 FOOT RUN MINIMUM.
12 INCHES MIN.
(30.5 CM)
GROUND LEVEL
UPWARD SLOPE ON HORIZONTAL VENT-COMMERCIAL INSTALLATION
NOTE - MINIMUM HORIZONTAL LENGTH 3 FT.
(914mm), NOT INCLUDING TEE FOR TER-
MINATION. REFER TO TABLE 2 FOR MAXI-
MUM LENGTH AND NUMBER OF ELBOWS.
COMMON VENTING NOT ALLOWED WHEN HORIZONTALLY VENTING THE UNIT HEATER.
(MAY USE WIRE MESH
BIRD SCREEN)
FIGURE 4
CONDENSATE DRAIN THROUGH TEE PIPE AND DRAIN LOOP
TEE PIPE
SECTION
DOWNWARD SLOPE ON HORIZONTAL VENT-COMMERCIAL INSTALLATION
DRAIN LOOP WITH WATER
TRAP (TO CONDESATE DRAIN)
NOTE-MINIMUM
HORIZONTAL LENGTH
3 FT. (914mm). REFER
TO TABLE 2 FOR
MAXIMUM LENGTH
AND NUMBER OF
ELBOWS.
COMMON VENTING
NOT ALLOWED WHEN
HORIZONTALLY
VENTENTING THE
UNIT HEATER.
LISTED THIMBLE
THROUGH
COMBUSTIBLE
WALL
MAY BE SINGLE WALL (26 GSG) GALV. OR EQUIV.
STAINLESS STEEL SEALED ACCORDING TO THESE
INSTALLATION INSTUCTIONS OR LISTED SPECIAL
VENT FOR CATEGORY III APPLIANCE.
SLOPE –1/4 INCH PER FOOT RUN MAXIMUM.
VENT
TERMINATION
TEE (MAY USE
WIRE
MESH BIRD
SCREEN)
12 INCHES
MIN. (30.5 CM)
