Installation Manual

24 440 01 4900 00
Specifications subject to change without notice.
Connect supply-- air duct to flanges on furnace supply-- air outlet.
Bend flange upward to 90_ with wide duct pliers. See Fig. 19. The
supply--air duct must be connected to ONLY the furnace
supply--outlet-- air duct flanges or air conditioning coil casing
(when used). DO NOT cut main furnace casing side to attach
supply air duct, humidifier, or other accessories. All supply--side
accessories MUST be connected to duct external to furnace main
casing.
Return Air Connections
The return--air duct may be connected to bottom of the furnace.
The side of casing that faces downward may also be used for return
air connection. A combination of the bottom and downward
facing side may also be used. The upward facing side of the casing
cannot be used as a return air connection. See Fig. 24.
Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return-- air opening. Remove and discard this panel when
bottom return air is used. To remove bottom closure panel, see Fig.
25 or 26.
Side Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return --air opening. This panel MUST be in place when
side return air inlet(s) are used without a bottom return air inlet.
Not all horizontal furnaces are approved for side return air
connections. See Fig. 24. Where required by code, seal bottom
closure to furnace with tape, mastic, or other durable sealing
method.
ANY COMBINATION OF 1, 2, OR 3 PERMITTED.
A11036
Fig. 22 -- Upflow Return Air Configurations and Restrictions
A11037
Fig. 23 -- Downflow Return Air Configurations
and Restrictions
HORIZONTAL TOP
RETURN NOT
PERMITTED FOR
ANY MODEL
A11038
Fig. 24 -- Horizontal Return Air Configurations
and Restrictions