Installation & Operation Manual
27
5
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.
Installation must comply with local
requirements and with the National Fuel
Gas Code, ANSI Z223.1 for U.S.
installations or CSA B149.1 for
Canadian installations.
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 in the
General Venting
section on
page 19 of this manual.
2.
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.
3.
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.
4.
The vent piping must terminate in an up-turned
coupling as shown in FIG. 5-1A. 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 FIG. 5-1B 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 above the air intake.
ALTERNATE INTAKE LOCATIONS:
INTAKE PIPES MAY BE LOCATED
ANYWHERE WITHIN 24” OF VENT
PIPE
BIRD SCREEN
(TYPICAL)
COUPLING
(FIELD SUPPLIED)
VENT OUTLET
12” MINIMUM
ABOVE AIR INLET
6” MINIMUM
ABOVE ROOF /
SNOW LINE
VENT
COMBUSTION
AIR
Figure 5-1A
PVC/CPVC Vertical Termination of Air and
Vent
5.
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.
WARNING
NOTICE
WARNING
Do not connect any other appliance to
the vent pipe or multiple boilers to a
common vent pipe. Failure to comply
could result in severe personal injury,
death, or substantial property damage.
WARNING
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 General Venting - Vertical
Vent, Sidewall Air Section.
6" (152 MM) MINIMUM
ABOVE ROOF /
SNOW LINE
VENT
COM,BUSTION
AIR
ALTERNATE INTAKE LOCATIONS:
INTAKE PIPES MAY BE LOCATED
ANYWHERE WITHIN 24” (610 MM)
OF VENT PIPE
VENT OUTLET
36” (914 MM) MINIMUM
ABOVE AIR INLET
BIRD SCREEN
(TYPICAL)
Figure 5-1B
Stainless Steel Vertical Termination of Air
and Vent
