Coleman PxXU-V series Installation Instructions Manual page 17

035-17468-001 Rev. A (801)
PIPING ASSEMBLY
The final assembly procedure for the vent/combustion air pip-
ing is as follows:
1. Cut piping to the proper length, beginning at the furnace.
2. Deburr the piping inside and outside.
3. Chamfer the outer edges of the piping.
4. Dry-fit the entire vent/combustion air piping assembly.
5. Disassemble the piping and apply cement primer and
cement per the cement manufacturer's instructions.
Primer and cement must conform to ASTM D2564 for
PVC, or ASTM D2235 for ABS piping.
Solvent cements are flammable and must be used in
well-ventilated areas only. Keep them away from
heat, sparks and open flames (including pilots). Do
not breathe vapors and avoid contact with skin and
eyes.
6. All joints must be made to provide a permanent, air-tight,
water-tight seal.
7. Support the combustion air and vent piping such that it is
angled 1/4" per linear foot so that condensate will flow
back toward the furnace. Piping should be supported
with pipe hangers to prevent sagging. Maximum spacing
between hangers is five (5) feet, except SDR-PVC pip-
ing, where maximum spacing is three (3) feet.
8. Seal around the openings where the combustion air and
vent piping pass through the roof of side wall.
Vent piping must be insulated with 1/2" Armaflex
insulation if it will be subjected to freezing
temperatures such as routing through unheated
areas or through an unused chimney.
When combustion air pipe is installed above a
suspended ceiling, the pipe must be insulated with
1/2" Armaflex type insulation. The combustion air
pipe should also be insulated when it passes
through a warm, humid space.
NOTE: Vent pipe must be sloped 1/4" per foot to allow con-
densate to flow back to the furnace.
METHOD TWO: ONE PIPE SYSTEM
This type installation will use combustion air from within the
space surrounding the furnace. This may be from within the
space in a non-confined location or it may be brought into the
furnace area from outdoors. It is not directly ducted into the
furnace. A single, properly sized pipe from the furnace vent
connector to the outdoors must be provided.
Unitary Products Group
For upflow models combustion air is brought into the furnace
through the unit top panel opening. Do not install a pipe into
the intake collar on top of the burner box. Refer to Figure 24.
COMBUSTION AIR
FIGURE 24 : Vent Pipe Connection - Upflow
For downflow/horizontal models combustion air is brought
into the furnace through the unit side panel openings.
COMBUSTION AIR
FIGURE 25 : Vent Pipe Connection -
Downflow/Horizontal
For downflow/horizontal models, remove a minimum of two
gas piping knockouts for combustion air access. Do not
install a pipe into the intake collar on bottom of the burner
box. For details, refer to Figure 25.
VENT PIPE CEMENTS
INTO SOCKET JUST
UNDER TOP PANEL
VENT PIPE PASSES
THROUGH TOP PANEL
GAS PIPING
KNOCKOUTS
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