Lennox 95G2UHV Installation Instructions Manual page 23

Figure 27. Typical Air Intake Pipe Connections in Upflow Direct Vent Applications
TYPICAL INTAKE PIPE CONNECTIONS IN HORIZONTAL DIRECT OR NON-DIRECT VENT
Figure 28. Typical Air Intake Pipe Connections in Horizontal Direct Vent Applications
Intake Piping
(Figure 27 through Figure 30)
This gas furnace may be installed in either direct vent
or non-direct vent applications. In non-direct vent
applications, when intake air will be drawn into the furnace
from the surrounding space, the indoor air quality must be
considered and guidelines listed in Combustion, Dilution
and Ventilation Air section must be followed
Follow the next two steps when installing the unit in Direct
Vent applications, where combustion air is taken from
507266-05
TYPICAL INTAKE PIPE CONNECTIONS IN UPFLOW DIRECT OR
NON-DIRECT VENT APPLICATIONS
2"
or
3"
AIR
TRANSITION
INTAKE
*2"
* When transitioning up in pipe size, use the shortest length of 2" PVC pipe possible.
NOTE: Exhaust pipe and intake pipe must be the same diameter.
APPLICATION (RIGHT-HAND DISCHARGE SHOWN)
* When transitioning up in pipe size, use the shortest length of 2" PVC pipe possible.
NOTE: Exhaust pipe and intake pipe must be the same diameter.
(Right Hand Discharge Shown)
Pipe size determined in Table 5
2"
2"
2"
2"
or
2"
2"
or
2"
2"
2"
AIR
INTAKE
outdoors and flue gases are discharged outdoors. The
provided air intake screen must not be used in direct vent
applications (outdoors).
1. Use transition solvent cement or a sheet metal screw
to secure the intake pipe to the inlet air connector.
2. Route piping to outside of structure. Continue with
installation following instructions given in general
guide lines for piping terminations and in intake and
exhaust piping terminations for direct vent sections.
Refer to Table 5A through Table 5C for pipe sizes.
Issue 1933
3"
TRANSITION
*2"
*2"
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