International comfort products C Series Installation Instructions Manual page 48

INSTALLATION INSTRUCTIONS
Combustion Air and Vent Piping Insulation
Guidelines
NOTE: Use closed cell, neoprene insulation or equivalent.
The vent pipe may pass through unconditioned areas. The
amount of exposed pipe allowed is shown in Table 16.
1. Using winter design
calculations), find appropriate temperature for your
application and furnace model.
2. Determine the amount of total and exposed vent pipe.
3. Determine required insulation thickness for exposed pipe
length(s).
4. When combustion air inlet piping is installed above a
suspended ceiling, the pipe MUST be insulated with
moisture resistant insulation such as Armaflex or other
equivalent type of insulation.
5. Insulate combustion air inlet piping when run in warm,
humid spaces.
6. Install the insulation per the insulation manufacturer's
installation instructions.
NOTE: Pipe length (ft / M) specified for maximum pipe lengths
located in unconditioned spaces (See Table 16) cannot exceed
total allowable pipe length as calculated from Table 14.
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.
Figure 56 Near Furnace Vent Connections
Avoid short horizontal offsets with 90
deg. Elbows. Short offsets can be
difficult to slope and may trap con-
densate.
48
temperature (used in load
Use 45 deg. Elbows where
possible, to ensure conden-
sate drainage.
L14F020A
Specifications subject to change without notice.
Slope vent pipe back to the
furnace at least ¼" per foot
Install the Vent and Combustion Air Pipes
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 12)
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 57 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 in the vent elbow to align it with the
inducer for each orientation.
3. Tighten the clamp around the vent elbow. Torque the
clamp to 15 lb-in. See Figure 58 through Figure 61.
Figure 57 Inducer Vent Elbow - - PSC
TABS ON THE INDUCER OUTLET RESTRICTOR SNAP
INTO THE SLOTS AT THE OUTLET OF THE INDUCER
FOR USAGE:
SEE MAXIMUM EQUIVALENT VENT LENGTH TABLE
Gas Furnace: N9MSB
L14F020B
PSC INDUCER ASSEMBLY
A14277A
A170006B
440 01 4104 07