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americanwaterheater .com
328767-001
STRAP (FIELD
SUPPLIED)
COMBUSTION
AIR
COMBUSTION
AIR
ORIENTATION OF EXHAUST PIPING AND COMBUSTION AIR PIPING RELATIVE
TO EACH OTHER MAY BE VERTICAL (AS SHOWN) OR AT ANY OTHER ANGLE
TO SUIT THE INSTALLATION.
ELBOW (FIELD
SUPPLIED)
SLOPE 1/4” OVER 5’
SCREEN INSIDE
EXHAUST
1” MAXIMUM
WALL
90° ELBOW
(SEE LOCAL
CODES)
PIPE NIPPLE (USE
WITH ELBOW)
Figure 24
VENT DIA.
P/N
2”
9008586005
3”
9006328005
Table 2
Figure 24 illustrates the concentric vent kit for a horizontal
(side wall) installation. To prevent rain water from entering
the exhaust outlet, slope the vent kit at a downward
pitch of 1/4” per 5’ away from the inside wall. Ensure the
combustion air intake location is above the anticipated
snow level.
Multiple Concentric Vent Installations
When two concentric vent kits are being installed, the vent
hood centers shall be
either
less than 9.5” apart
or
more
than 43.5” apart. Spacings between 9.5” and 43.5” are not
allowed due to the possibility of exhaust cross circulation
(see Figure 25).
When more than 2 kits are installed only 2 of them shall
be less than 9.5” apart. Never install 3 termination kits
together less than 9.5” apart (see Figure 26).
9.5” MAX OR
43.5” MIN
WALL
SCREEN
NOTE: IF AN
ELBOW IS
REQUIRED
BY LOCAL
CODES
INSTALL
SCREEN
IN ELBOW
INSTEAD OF
CONCENTRIC
VENT
EXHAUST.
Figure 25
43.5” MIN.
9.5” MAX..
WALL
NOTE: IF AN ELBOW IS REQUIRED BY
LOCAL CODES INSTALL SCREEN IN ELBOW
INSTEAD OF CONCENTRIC VENT EXHAUST.
SCREEN
Figure 26
Vent Pipe Length
The maximum allowable pipe lengths for air intake and
exhaust are listed in Table 3. The speci
fi
ed maximum
lengths are for
each
of the intake and exhaust systems and
not
for the combined lengths of both systems. In addition,
each system requires a 45° long sweep elbow termination
with a restrictive screen. Minimum pipe length is 3’ with a
minimum of one 90° elbow per side (intake and exhaust).
1. Determine termination type and pipe size.
2. Determine number of elbows in vent system. Do not
include termination elbow. Calculate the maximum
equivalent length of the exhaust and air intake system.
90° LONG SWEEP ELBOW
(LESS RESTRICTIVE)
90° SHORT SWEEP ELBOW
(MORE RESTRICTIVE)
Figure 27
