User Guide

28
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 in. OVER
5 ft.
SCREEN INSIDE
EXHAUST
1 in. MAXIMUM
WALL
90° ELBOW
(SEE LOCAL
CODES)
PIPE NIPPLE (USE
WITH ELBOW)
Figure 25
VENT DIA. P/N
3” 9006328005
Table 2
Figure 25 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 in. per 5 ft. 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 in. apart
or more than 43.5 in. apart. Spacings between 9.5 in. and
43.5 in. are not allowed due to the possibility of exhaust
cross circulation (see Figure 26).
When more than 2 kits are installed only 2 of them shall
be less than 9.5 in. apart. Never install 3 termination kits
together less than 9.5 in. apart (see Figure 27).
9.5 in. MAX OR
43.5 in. MIN
WALL
SCREEN
NOTE: IF AN
ELBOW IS
REQUIRED
BY LOCAL
CODES
INSTALL
SCREEN
IN ELBOW
INSTEAD OF
CONCENTRIC
VENT
EXHAUST.
Figure 26
4
3.5 in.
MIN.
9.5 in
MAX..
WALL
NOTE: IF AN ELBOW IS REQUIRED BY
LOCAL CODES INSTALL SCREEN IN ELBOW
INSTEAD OF CONCENTRIC VENT EXHAUST.
SCREEN
Figure 27
Vent Pipe Length
The maximum allowable pipe lengths for air intake and
exhaust are listed in Table 3. The specifi 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 ft. 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 28