Haier GE NF96DS Service Manual page 28

Intake Piping
The NF96DS 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
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
guidelines for piping terminations and intake and
exhaust piping terminations for direct vent sections.
Refer to Table 10A through Table 11B for pipe sizes.
Follow the next two steps when installing the unit in Non-
Direct Vent applications where combustion air is taken
from indoors and flue gases are discharged outdoors.
1. Use field-provided materials and the factory-provided
air intake screen to route the intake piping as shown in
Figure 24. Maintain a minimum clearance of 3" (76mm)
around the air intake opening. The air intake opening
(with the protective screen) should always be directed
forward, or sideways.
2. If intake air is drawn from a ventilated attic (Figure 25)
or ventilated crawlspace (Figure 26) the exhaust vent
length must not exceed those listed in Table 11A through
Table 11B. If 3" diameter pipe is used, reduce to 2"
diameter pipe at the termination point to accommodate
the debris screen.
3. Use a sheet metal screw to secure the intake pipe to the
connector, if desired.
NOTE: Debris screen and elbow may be rotated so that the
screen may be positioned to face forward or to either side.
Figure 24. Typical Air Intake Pipe Connections
Non-Direct Vent Applications
If this unit is being installed in an application with
combustion air coming in from a space serviced by an
exhaust fan, power exhaust fan, or other device which
may create a negative pressure in the space, take care
when sizing the inlet air opening. The inlet air opening
must be sized to accommodate the maximum volume
of exhausted air as well as the maximum volume of
combustion air required for all gas appliances serviced
by this space.
Roof Terminated
Exhaust Pipe
* See Maximum Vent Lengths table
NOTE-The inlet and outlet air openings shall each have a
free area of at least one square inch per 4,000 Btu (645mm
per 1.17kW) per hour of the total input rating of all equipment
in the enclosure.
Figure 25. Equipment in Confined Space
(Inlet Air from Ventilated Attic and Outlet Air to
Page 28
Intake
Debris
Screen
(Provided)
CAUTION
Ventilation Louvers
Inlet Air
(Minimum 12 in.
(305mm) above
Attic Floor)
*Intake Debris
Screen
(Provided)
Furnace
2
Outside)
31-5000729 Rev. 0