Carrier 58MXA Nstallation, Start-Up, And Operating Instructions page 25

VENT PIPE
HORIZONTAL TO ROOF
COMBUSTION-AIR PIPE
VERTICAL TO ROOF
f. Install casing hole filler cap (factory-supplied in loose parts
bag) in unused combustion-air pipe casing hold.
g. Drill a 1/8-in. hole in 2-in. combustion-air pipe using hole
in intake housing as a guide.
h. Install a field-supplied No. 6 or No. 8 sheet metal screw
into combustion-air pipe.
NOTE: DO NOT OVERTIGHTEN SCREW. Breakage to intake
housing or fitting may cause air leakage to occur.
NOTE: Do not attach combustion-air intake pipe permanently to
combustion-air intake housing since it may be necessary to remove
pipe for service of ignitor or flame sensor.
COMBUSTION-AIR INTAKE HOUSING PLUG FITTING
The combustion-air intake plug fitting must be installed in unused
combustion-air intake housing. This fitting must be attached by
using RTV sealant, or by drilling a 1/8-in. hole in fitting, using
hole in intake housing as a guide. Install a field-supplied No. 6 or
No. 8 sheet metal screw.
NOTE: DO NOT OVERTIGHTEN SCREW. Breakage to intake
housing or fitting may cause air leakage to occur.
A plugged drain connection has been provided on this fitting for
use when moisture is found in combustion-air intake pipe and
combustion box.
NOTE: Moisture in combustion-air intake may be result of
improper termination. Ensure combustion-air intake pipe is similar
12 " MIN
COMBUSTION-AIR PIPE
12 " MIN
NOTE: A 12 In. minimum offset pipe section is recommended with
short (5 to 8 ft) vent systems. This recommendation is to reduce
excessive condensate droplets from exiting the vent pipe.
Fig. 34—Short Vent (5 to 8 Ft) System
VENT PIPE
HORIZONTAL TO SIDEWALL
COMBUSTION-AIR PIPE
VENT PIPE
VERTICAL TO SIDEWALL
to that shown in Fig. 36, 37, 38, 39, and 40 so it will not be
susceptible to areas where light snow or other sources of moisture
could be pulled in.
If use of this drain connection is desired, drill out fitting's tap plug
with a 3/16-in. drill and connect a field-supplied 3/8-in. tube. This
tube should be routed to open condensate drain for furnace and
A/C (if used), and should be trapped. (See Fig. 35.)
3/8" ID TUBE
3/16"
DRILL
4"
MIN
TRAP
TO OPEN
DRAIN
Fig. 35—Intake Housing Plug Fitting Drain
25
12 " MIN
COMBUSTION-AIR PIPE
12 " MIN
VENT PIPE
COMBUSTION – AIR
INTAKE HOUSING
BURNER
BOX
COMBUSTION –
AIR PIPE
A96230
A93035