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DIRECT VENT COLINEAR VENT EXAMPLES
Note:
Exhaust must be a
minimum of 3 inches above
air intake inlet.
Max Vent Run - 40 ft. Equivalent With Three three 90° Elbows
Special Note: The vent terminal 90° elbow and first 90° elbow
off back of the fireplace, when within 6” (15.2 cm), do not con-
tribute to the overall vent length measurement. For each 45°
elbow installed in the horizontal run, the length of the hori-
zontal run MUST be reduced by 1.5 feet (45 cm). This does not
apply if the 45° elbows are installed on the vertical part of the
vent system. Reduce the length of the horizontal run 3 feet
(91.4 cm) for every 90° elbow.
Figure 15
Calculation example of vent run maximum 40 feet
Figure 15 displays a two-pipe installation. Because the distance
from the fireplace to the first elbow is more than 6 inches, the
equivalent length allowance for the first 90° elbow must be added
to the total vent length. The equivalent length of the second 90°
elbow also needs to be added to the total length. The third el
-
bow also needs to be included. The equivalent length of the PTrap
does not need to be added since it is the termination. The total
horizontal vent length of the flue system is 11 feet, and the total
vertical length is 20 feet. The three 90° elbows are equivalent to 9
feet, bringing the total to 40 feet.
Note:
The exhaust must be a minimum of 3 inches above the inlet
air pipe. The flue must be at least 12 inches from the roof line, and
it is recommended to be at least 12 inches above the maximum
expected snow level as indicated in Figures 7, 9, 13, 14, 16 and
20.
Note:
On horizontal runs, a P.V.C. support clamp needs to be in
-
stalled every 3 feet. Do not allow “sags” in horizontal vent runs;
water will settle in the pipe.
When installing a colinear horizontal, the minimum vent length
protruding from the outside wall is 6” (15.2 cm) for air intake and 9”
for exhaust. See Figure 16.
Note:
Horizontal discharge 90° elbow must be pointed downward.
See Figure 16. All horizontal runs require either a 1/4” per foot rise
to run condensation back to the fireplace, or a 1/4” per foot down
-
ward slope to run condensation away from the fireplace.
Note:
All PVC vent run piping can be purchased at a local hard
-
ware store. Schedule 40 PVC pipe should be used and cemented.
PVCA Horizontal Colinear Direct Vent Adaptor, PVVTC Cap, PV
-
VK-CFA Flex Kit and PVVK-SH Horizontal Vent Adaptor Kit are
available from Empire Comfort Systems, Inc.
In both vertical and horizontal colinear direct vent applications,
a colinear transition plate model PVCT can be used to minimize
clearances between intake and exhaust pipes.
For horizontal colinear direct venting, exhaust and intake air, cap
pipes with 90º elbows, pointed downward.
Note
: If transition plate (model PVCT) is used, the measurement
for center to center of the pipes will be 2.5”. If the transition plate
(model PVCT) is not used, the measurement for center to center
of the pipes can be 3” to 24” maximum.
Figure 16