Carrier 58UXT Series Operating Instructions Manual Download

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RETURN AIR CONNECTIONS

For airflow requirements above 1800 CFM, see Air Delivery
table in Product Data literature for specific use of single side
inlets. The use of both side inlets, a combination of 1 side and
the bottom, or the bottom only will ensure adequate return air
openings for airflow requirements above 1800 CFM.

Upflow Furnaces

The return-air duct must be connected to bottom, sides (left or
right), or a combination of bottom and side(s) of main furnace
casing as shown in Fig. 1. Bypass humidifier may be attached into
unused side return air portion of the furnace casing. DO NOT
connect any portion of return-air duct to back of furnace casing.

Horizontal Furnaces

The return-air duct must be connected to return-air opening (inlet)
provided as shown in Fig. 1. DO NOT cut into casing sides or back
to attach any portion of return-air duct. Bypass humidifier connec-
tions should be made at ductwork or coil casing sides exterior to
furnace.

Step 2—Filter Arrangement

Never operate unit without a filter or with filter access door
removed. A failure to follow this warning can cause a fire,
personal injury, or death.

The air filter arrangement will vary due to application and filter
type. The filter may be installed in an external Filter/Media cabinet
(if provided) or the furnace blower compartment. Factory supplied
washable filters are shipped in the blower compartment.

If a factory-supplied external Filter/Media cabinet is provided,
instructions for its application, assembly, and installation are
packaged with the cabinet. The Filter/Media cabinet can be used
with the factory- supplied washable filter or a factory-specified
high-efficiency disposable filter (see cabinet instructions).

If installing the filter in the furnace blower compartment, deter-
mine location for the filter and relocate filter retaining wire if
necessary. After the return-air duct has been connected to the
furnace, install the filter(s) inside the furnace blower compartment.
See Fig. 7 for side return application and Fig. 8 for bottom return
application.

A bottom closure panel is factory installed in the bottom of the
furnace. When bottom return inlet is desired, remove and discard
the enclosure panel.

Filter retaining brackets, supports, and retainers are factory as-
sembled and shipped installed for side return application, with 1
set of all required hardware on each furnace. (See Fig. 7.)

For bottom return applications, remove the front and back brackets
and supports from each side. The back bracket(s) are installed in
the rear of the furnace casing. Dimples are provided to mark
mounting screw locations.

The front bracket(s) are installed on the bottom front plate, as
shown in Fig. 6, once the bottom enclosure has been removed.
Rotate filter supports 180 so filter will rest on support and reinstall.
Install small U-shaped end of filter retaining rod in the rear
bracket. Install the front of filter retainer rod as shown in Fig. 8.
Two sets of hardware are needed for furnaces in 24-1/2 in. casings
using 2 filters for bottom return. All hardware is provided for filter
installation.

Fig. 7—Side Filter Arrangement

A95284

FILTER

RETAINER

WASHABLE
FILTER

Fig. 8—Bottom Filter Arrangement

A00290

WASHABLE
FILTER

FILTER
SUPPORT

FILTER
RETAINER

⁄

-IN. WIDE