![background image](http://html1.mh-extra.com/html/empire-comfort-systems/pv-28sv50-b2hn-1/pv-28sv50-b2hn-1_owners-manual_2403976019.webp)
24820-2-0709
Page 19
VENT EXAMPLES FOR SINGLE FLUE
Max Vent Run - 40 ft. Equivalent With Three (3) 90° Elbows
Special Note: The vent terminal 90° elbow and first 90° elbow off back of the heater, when within 6” (15.2 cm), do not
contribute to the overall vent length measurement. For each 45° elbow installed in the horizontal run, the length of the
horizontal 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.
Note:
On horizontal runs, a P.V.C. support clamp needs to be installed every 3 feet. No “sags” in horizontal vent runs; water will settle
in the pipe.
When installing a single flue horizontal, the minimum vent length protruding from the outside wall is 6” (15.2 cm). See Figure 17.
Minimum vent from the rear of the unit is 12”.
Note:
Horizontal discharge 90° elbow must be pointed downward. See Figure 18. All horizontal runs require either a 1/4” per foot rise
to run condensation back to the heater, or a 1/4” per foot downward slope to run condensation away from the heater.
Note:
All PVC vent run piping can be purchased at a local hardware store. Schedule 40 PVC pipe should be used and cemented.
PVVK-CFA Flex Kit and PVVK-SH Horizontal Vent Adaptor Kit are available from Empire Comfort Systems, Inc.
Figure 17
Single Flue - Straight Out Back
Min 6” Outside Wall
Min 2” From Unit to Wall for Intake Air
Min vent length 12”
Figure 18
Single Flue - Horizontal Tall Vent Run
Example Calculation Max Vent Run 40’
H =
5’ + 2’ = 7’
V =
27’
(2) - 90° = 6’
Total =
40’
EXTERIOR GRADE
12” MIN.
6” MIN.
MIN. 2”
12” MIN.