27297-5-0511
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VENT EXAMPLES FOR SINGLE FLUE
Figure 3 displays a single flue (one-pipe) installation. Be
-
cause the distance from the heater to the first elbow is more
than 6 inches, the first 90° elbow does need to be consid
-
ered into the total vent length. The equivalent length of the
second 90° elbow also needs to be added to the total length,
but the third elbow does not since it is the flue terminal. The
total horizontal vent length of the flue system is 7 feet, and
the total vertical length is 27 feet. The two 90° elbows are
equivalent to 6 feet, bringing the total to 40 feet.
Figure 4 is an example of how the heater can be vented if
the flue outlet is below the level of the floor.
2’
5’
27’
VENT TERMINAL
90° ELBOW
(NOT COUNTED)
90° ELBOW
3’
FIRST 90° ELBOW
DOES NOT GET COUNTED
WHEN WITHIN 6”
OFF BACK OF HEATER
Figure 3
Single Flue - Horizontal Tall Vent Run
Example Calculation Max Vent Run 40 feet
H =
5’ + 2’ = 7’
V =
27’
(2) - 90° = 6’
Total =
40’
Figure 4
Minimum Exterior Grade Dimension - Single Flue, Hori-
zontal Venting Below Floor
