8
W415-0098 / C / 04.19.06
57"
first run
72"
second run
48"
Use the chart on this page to calculate horizontal runs for
vertical rises between 29 and 57 inches. FIGURE 7.
When calculating maximum run lengths, include 10 feet for
each 90° elbow or 5 feet for each 45° elbow.
(DO NOT INCLUDE THE FIRST ELBOW DIRECTLY OFF
THE UNIT.)
When a horizontal run is introduced, even though the termi-
nal may be vertical, the installation must be considered
HORIZONTAL.
A through the roof installation requires a total 5 foot rise.
FIGURE 8. The location of the fireplace dictates a horizontal
run of 5 feet. What is the required vertical rise to the centre
of the initial 90° elbow?
The total run is:
5 ft. (through the roof vertical rise)
10 ft. (90° elbow)
5 ft. (horizontal run)
20 ft. (total run)
Using the chart, will determine
that a 57 inch minimum vertical
rise immediately off the unit is
required for satisfactory venting
conditions.
ALTHOUGH THE IMMEDIATE
VERTICAL RUN MAY BE
GREATER THAN 57 INCHES, THE
MAXIMUM COMBINATION OF
HORIZONTAL AND VERTICAL
RUNS, BEYOND THE 57 INCHES,
MUST NOT EXCEED 20 FEET.
If a first run of 72 inches is
required, using the "First Vent
Run" on the chart shows that
a maximum second run of
48 inches is allowable.
IF NECESSARY, THE
FIRST RUN AND THE
SECOND RUN MAY BE
REVERSED.
FIGURE 9
FIGURE 10
FIGURE 7
CALCULATED HORIZONTAL VENT RUN IN FEET
REQUIRED
V E R T I C A L
RISE FROM
FIREPLACE
TO FIRST
ELBOW IN
INCHES
FIGURE 8
SPECIAL INSTALLATION EXAMPLE
OFFSET INSTALLATION EXAMPLE
