59SP6A: Installation, Start-up, Operating, Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
18
A10491
Fig. 25 – Installation on Combustible Flooring
Connect supply-air duct to flanges on furnace supply-air outlet. Bend
flange upward to 90° with wide duct pliers. See
. 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
.
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
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
. Where required by code, seal bottom closure to furnace with
tape, mastic or other durable sealing method.
Filter Arrangement
There are no provisions for an internal filter rack in these furnaces. An
external filter is required.
This furnace may use an optional Media Filter Cabinet available from
your local distributor. The Media Filter Cabinet uses either a standard
1-inch (25 mm) filter or 4-inch (102 mm) wide Media Filter which can
be purchased separately.
The Media Cabinet is sized for bottom return applications for use in
upflow, downflow and horizontal applications.
For upflow side return applications, the Media Cabinet or field supplied
accessory air cleaner can be installed on the side of the furnace or side
and bottom when a bottom plenum is used. See
.
For downflow applications, the Media Cabinet or field supplied
accessory air cleaner must only be connected to the bottom opening on
and
For horizontal applications, the Media Cabinet or field supplied
accessory air cleaner for all models can be connected to the bottom
opening on the furnace. For side return use in the horizontal position,
refer to
. If both side and bottom openings are used in
each opening used will require a filter.
The media cabinet or field supplied accessory air cleaner can also be
installed in the common return duct prior to entering the return air
opening in any orientation.
Refer to the instructions supplied with Media Cabinet or accessory air
filter for assembly and other details.
See
for filter size details.
Table 6 – Air Filter Selection and Duct Sizing - In. (mm)
Filter and Return Duct Sizing
Pressure drop must be taken into account when sizing filters, filter racks,
IAQ devices, and associated system ductwork. See
for a
comparison of Pressure Drop (initial/clean resistance to airflow) versus
Airflow for a variety of filter media types and sizes. These are
representative numbers. Consult the filter or IAQ device manufacturers’
PLENUM
OPENING
C
A
B
D
FLOOR
OPENING
DOWNFLOW
SUBBASE
SHEET METAL
PLENUM
FLOOR
OPENING
FURNACE
(OR COIL CASING
WHEN USED)
COMBUSTIBLE
FLOORING
APPROVED
COIL ASSEMBLY
OR
COIL BOX
FURNACE
SHEET METAL
PLENUM
FLOOR
OPENING
COMBUSTIBLE
FLOORING
WARNING
!
FIRE, CARBON MONOXIDE AND POISONING
HAZARD
Failure to follow this warning could result in fire, personal injury or
death.
Never operate a furnace without a filter or filtration device installed.
Never operate a furnace with filter or filtration device access doors
removed.
FILTER
CABINET
HEIGHT
IN (MM)
FILTER SIZE - IN (MM)
FILTER TYPE
14-3/16
*
(360)
*. Not all families have these models.
14 x 25 x 3/4
(356 x 635 x 19)
Washable
or Media
†
†. Filters with a side return-air may have a different filter size. Measure the
filter to obtain the correct size.
Recommended to maintain air filter face velocity. See Product Data for part
number
16 (406)
(1) 16 x 25 x 3/4*
(406 x 635 x 19) or
(1) 16 x 25 x 4-5/16
(406 x 635 x 110)
Washable
or Media
21 (533)
(1) 20 x 25 x 3/4*
(508 x 635 x 19) or
(1) 20 x 25 x 4-5/16
(508 x 635 x 110)
Washable
or Media
24-1/2 (622)
(1) 24 x 25 x 3/4*or
(610 x 635 x 19) or
(1) 24 x 25 x 4-5/16
(610 x 635 x 110)
Washable
or Media