Vertical Direct Venting - Smith XWH 150 Instruction Manual

VERTICAL DIRECT VENTING

VENT/ AIR TERMINATION - VERTICAL
Follow instructions below when determining vent location to
avoid possibility of severe personal injury, death or substantial
property damage.
DETERMINE LOCATION
Locate the vent/air terminations using the following guidelines:
1. The total length of piping for vent or air must not exceed the
limits given on Table 9 of this manual.
2. Prepare the vent termination and the air termination elbow
(Figure 43) by inserting bird screens. Bird screens should be
obtained locally.
3. The vent must terminate at least 3 feet above the highest
place in which the vent penetrates the roof and at least 2 feet
above any part of a building within 10 horizontal feet.
4. The air piping must terminate in a down-turned 180° return
pipe no further than 2 feet from the center of the vent pipe.
This placement avoids recirculation of flue products into the
combustion air stream.
5. The vent piping must terminate in an up-turned coupling as
shown in Figure 43. The top of the coupling must be at least
1 foot above the air intake. When the vent termination uses
a rain cap as illustrated in Figure 44 maintain at least 36"
(914 mm) above the air inlet. The air inlet pipe and vent pipe
can be located in any desired position on the roof, but must
always be no further than 2 feet (.6 m) apart and with the vent
termination at least 1 foot for PVC and 3 feet for stainless
steel, above the air intake.
6. Maintain the required dimensions of the finished termination
piping as shown in Figure 43.
7. Do not extend exposed vent pipe outside of building more
than shown in this document. Condensate could freeze and
block vent pipe.
Rooftop vent and air inlet terminations must terminate in the
same pressure zone, unless vertical vent sidewall air is set up as
shown in the Vertical Vent, Sidewall Air section.
8. Locate terminations so they are not likely to be damaged by
foreign objects, such as stones or balls, or subject to buildup
of leaves or sediment.
Figure 43. PVC/CPVC Vertical Termination of Air and Vent
Figure 44. Stainless Steel Vertical Termination of Air and
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Vent