International comfort products R9MSB0801716 Installation Instructions Manual page 45

INSTALLATION INSTRUCTIONS
Configure the Furnace
WARNING
!
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal
injury or death.
To route the vent pipe and combustion air pipe
through the furnace, the manufacturer supplied kit
must be used. Failure to properly seal the blower
compartment from the furnace vestibule could result
in the circulation of carbon monoxide throughout the
structure. The vent pipe and combustion air pipe must
be a continuous pipe while passing through the
blower compartment. Seals supplied in this kit must
be installed per the instructions provided. Follow all
procedures outlined in these instructions.
Near Furnace Vent Connections
Offsets in the vertical portion of the vent pipe should be made
with 45 degree elbows instead of 90 degree elbows. Short
horizontal runs of vent pipe are difficult to pitch correctly and
may trap water in the vent pipe. Trapped water in the vent pipe
may result in nuisance pressure switch tripping.
Avoid short horizontal offsets with 90
deg. Elbows. Short offsets can be
difficult to slope and may trap con-
densate.
Slope vent pipe back to the
furnace at least ¼" per foot
Figure 42 − Combustion−Air and Vent Pipe Diameter
Transition Location and Elbow Configuration
440 01 6001 05
Use 45 deg. Elbows where
possible, to ensure conden-
sate drainage.
L14F020A
L14F020B
Specifications subject to change without notice.
Install the Vent and Combustion Air Pipe
With the furnace installed in the required position, remove the
desired knockouts from the casing. It will be necessary to
remove one knockout for the vent pipe and the other knockout
for the combustion air connection. (See Figure 14.)
Use a flat blade screwdriver and tap on the knockout on
opposite sides, where the knockout meets the casing. Fold the
knockout down with duct pliers and work the knockout back
and forth until it is removed. Trim any excess metal from the
knockout with tin snips.
The vent elbow can be rotated to the required location on the
casing if necessary. See Figure 44. To rotate the vent elbow:
1. Loosen the clamp on the inlet of the vent elbow attached
to the inducer.
2. Rotate the vent elbow to the required position. There are
rounded notches on the vent elbow to align it with the
inducer housing for each orientation.
3. Tighten the clamp around the vent elbow. Torque the
clamp to 15 lb−in. See Figure 46−Figure 49.
Installing the Vent Pipe Adapter and
Combustion Air Pipe Adapter
WARNING
!
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal
injury or death.
To route the vent pipe and combustion air pipe
through the furnace, the manufacturer supplied kit
must be used. Failure to properly seal the blower
compartment from the furnace vestibule could result
in the circulation of carbon monoxide throughout the
structure. The vent pipe and combustion air pipe
must be a continuous pipe while passing through the
blower compartment. Seals supplied in this kit must
be installed per the instructions provided. Follow all
procedures outlined in these instructions.
WARNING
!
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal
injury or death.
DO NOT use cement to join polypropylene venting
systems. Follow the polypropylene venting system
manufacturer's instructions for installing polypropylene
venting systems.
NOTE: The rubber coupling that attaches to the vent pipe
adapter must be used. The adapter seals the vent pipe to the
casing and reduces the strain on the vent elbow attached to the
inducer.
1. Apply the gaskets to the vent pipe and combustion air
pipe adapters. If supplied, remove and discard round
center "slug" from interior of gasket. See Figure 43.
NOTE: The vent pipe adapter can be distinguished from the
inlet pipe adapter by the absence of an internal pipe-stopping
ring. The vent pipe can pass through the vent pipe adapter; it
cannot pass through the inlet pipe adapter.
2. Align the screw holes in the plastic vent pipe adapter with
the dimples in the casing.
Gas Furnace: R9MSB
45